captioning sponsored by newshour productions, llc >> brangham: good evening. i'm william brangham. judy woodruff is off today. on the newshour tonight: a war of words. the president says steve bannon has "lost his mind," after his former chief strategist describes a meeting between the trump campaign and some russians as "treasonous." then, a week of unrest in iran. we get the latest from tehran on what sparked the nationwide protests. and, how to avoid the drill at the dentist. we examine a new technique in the fight against cavities. >> the silvery liquid in this little bottle has lead to some big changes recently in the way some tooth decay is being treated. >> brangham: plus, for all you book lovers, we are excited to announce, the newshour is teaming up with the "new york times" and viewers like you, for a new book club. all that and more, on tonight's

pbs newshour. >> major funding for the pbs newshour has been provided by: ♪ ♪ moving our economy for 160 years. bnsf, the engine that connects us.

>> "the post," in theaters everywhere january 12. >> babbel. a language app that teaches real-life conversations in a new language. >> supporting social entrepreneurs and their solutions to the world's most pressing problems-- skollfoundation.org. >> the lemelson foundation. committed to improving lives through invention, in the u.s. and developing countries. on the web at lemelson.org. >> supported by the john d. and catherine t. macarthur foundation. committed to building a more just, verdant and peaceful

world. more information at macfound.org >> and with the ongoing support of these institutions: >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> brangham: there's a new storm at the trump white house tonight, and steve bannon is at its center. a new book quotes him saying president trump never expected to win the election, and that it was "treasonous" for donald trump jr. to meet with a russian lawyer in 2016. the president shot back at his former chief strategist in a statement, saying, "when he was fired, he not only lost his job, he lost his mind." white house press secretary sarah sanders dismissed the allegations, and said mr. trump is justifiably angry. >> i think, furious, disgusted would probably certainly fit, when you make such outrageous claims and completely false claims against the president,

his administration and his family. >> brangham: we'll delve into this more deeply, after the news summary. in the day's other news, former trump campaign chair paul manafort sued the justice department and special counsel robert mueller, who's leading the russia investigation. manafort has been charged with failing to register as a foreign agent, working for ukraine. he argues investigators overstepped their bounds by indicting him for conduct unrelated to russian interference in the election. iran's elite revolutionary guards has now deployed to three provinces to put down protests that began a week ago. at least 21 have dies, and the unrest kept spreading today, even as officials organized major rallies to support the government. we'll have a full report, later in the program. north korea reopened a cross- border communications channel with south korea today, for the first time in nearly two years. at the same time, new taunts flew between washington and

pyongyang. on monday, kim jong-un warned that he had a "nuclear button" and his weapons could reach all of the u.s. mainland. president trump responded last night, saying, "i too have a nuclear button, but it is a much bigger and more powerful one than his, and my button works!" palestinian officials are condemning what they say is "blackmail" by president trump. he charged yesterday the palestinians are not doing enough to make peace with israel, and he suggested cutting u.s. funding to the palestinian authority. today, palestinian leaders said it's mr. trump who sabotaged the peace process, by recognizing jerusalem as israel's capital. >> i would say that palestinian rights are not for sale and we will not succumb to blackmail. there are imperatives and requirements for peace, and unilaterally, president trump has destroyed them. he has even sabotaged our efforts at achieving a just peace and getting freedom and dignity for the palestinian people. >> brangham: congress estimates the u.s. provides an average of $400 million a year in economic aid to palestinians in the west bank and gaza.

ethiopia has announced it's releasing political prisoners and closing a prison camp in the wake of anti-government protests. the prime minister's surprise announcement marked the first time the government admitted to holding political prisoners. a violent storm swept across western europe today, knocking out power, disrupting transportation and killing one person. wind gusts up to 100 miles an hour battered towns across france, britain, ireland and switzerland, uprooting trees and flooding coastlines. several hundred thousand homes have lost power. the storm also derailed trains, halted highway traffic in places and grounded thousands of flights. the u.s. deep south is still reeling from a rare winter storm that dumped snow and freezing rain along the coast today. it shut down interstates and airports, and dropped the first snow in tallahassee, florida in decades. as much as three inches of snow

fell in charleston, south carolina and parts of coastal georgia. north carolina governor roy cooper warned of treacherous conditions. >> we expect that travel will be difficult and dangerous, with power outages that are possible. the good news is that the storm is moving quickly, should be gone by thursday evening. the bad news is that unusually cold temperatures are sticking around for several days. >> brangham: the worst could come tomorrow as the storm moves north. hurricane-force winds are forecast, with blizzard conditions in new england. a dry winter in california has sparked new concerns of another drought. water officials today measured little snow in the sierra nevada mountains, which can supply the officials said it's not yet time to panic, as it is still early in the rain season, and record rainfall last year left reservoirs with plenty of water. the u.s. senate now has two new democratic members. doug jones of alabama and tina smith of minnesota were sworn in

today at the capitol, as the senate formally began its 2018 session. jones is the first democrat in a quarter-century to win a senate seat in alabama. his election narrows the republican majority to 51-49. smith was appointed to fill al franken's seat, after he stepped down amid allegations of sexual misconduct. on wall street today, health care and tech stocks pushed the overall market higher. the dow jones industrial average gained 98 points to close at 24,922. the nasdaq rose 58 points, and the s&p 500 added 17, to top 2,700 for the first time. and, the president of the mormon church, thomas monson, passed away last night. monson served in top leadership councils for the church for more than 50 years, and became president in 2008. he was known for emphasizing humanitarian work and for leading the church's opposition to same-sex marriage. thomas monson was 90 years old. still to come on the newshour: what role the russia investigation is playing in the

public rift between president trump and steve bannon. how the president's tweets on foreign policy resonate around the world. a new, low-cost way to fight cavities. and, much more. >> brangham: we return to the public rift today between president trump and his former chief strategist, steve bannon. hari sreenivasan explores how the spat was sparked by the russia investigation. >> sreenivasan: in excerpts of an upcoming book on the trump presidency, steve bannon is quoted as calling a june 2016 meeting that donald trump jr. and other campaign aides held with a group of russians as "treasonous" and "unpatriotic." separately, another focus of the russia investigation returned to the headlines, after two founders of fusion g.p.s., a political research firm that commissioned the so-called

steele dossier, wrote an op-ed for the "new york times." we breakdown these latest twists and turns with mark mazzetti, washington investigations editor for the "new york times;" and robert costa, host of "washington week" and national political reporter for the "washington post." robert, we saw the white house come out very strongly against steve bannon today. steve had very little to do with their historic victory, was one of the quotes they put out in the statement. not only did he lose his job, but he also lost his mind. put steve bannon in perspective here on how important or what kind of role he played in the campaign and in the presidency. >> a strong and visceral response from president trump and his advisors today, it is the culmination of a somewhat winding path that was taken by bannon ever since he was chief strategist at the white house, in 2017. he departs last summer. he remained in close contact with president trump in recent months talking through issues

like the alabama senate race, but after this new book by michael wolf, people close to the president tell me they don't expect him to speak to bannon anytime soon. they feel burned about the comments he's made especially about the president and the president's family. >> sreenivasan: i was going to say, what does this tell us about the president? because there seems to be lots of different thresholds of critique that he can withstand. >> it tells us the president fights as he did in the 1980s and '90s, still now in a compattive tabloid style. he doesn't mind these comments that bannon has lost his mind. but there is an asterisk when it comes to president trump. if you look to roger stone and many business associates, he has quoan to war with people in the past and mended the relationships and continued to talk to people. so i'm not ready to write off bannon as a reporter and say he's totally outside the president's inner circumstance bull certainly this is a major

new bump in that relationship. >> sreenivasan: the meeting in trump tower between donald trump, jr. and some of the russians was one of the focal points of the russia investigation but the other was dossier written by fusion g.p.s. mark mazzetti, bring us up to speed on what was in there and other reporting they had. >> the dossier was commissioned by the firm fusion g.p.s. and they hired a former british spy christopher steele to put together information and research any connections between donald trump and russia. this occurred over 2016, and, at the very beginning of 2017, almost exactly a year ago, it became public when buzz feed published the dossier and it was sort of a wide-ranging series of accusations about trump's relations with the russians. some charges were quite salacious, and it has quite hung over this story for the better part of a year, this question of is what is in the dossier true,

and it is also those that we come a kind of cudgel by the republicans to try to beat back the issue of trump and russia, they're trying to paint the dossier as a political opposition hired by hillary clinton and the democrats, and as a political document rather than as a piece of intelligence. >> sreenivasan: mark, there's also this back and forth on who wants what public and in what forum, right? i mean, the people at fusion g.p.s. says their reporting and their research uncovered money laundering and other links between the president and russians, and they said they would prefer to have all their testimony presented to congress which might not have been in the dossier to be public and, at the same time, we have members of congress saying, fine, the invitation for you to be public is open. >> right, so they've already testified before congress and as they said in the op-ed, they would like transcripts of the testimony released. that will be up to the discretion of members of congress to do so and you saw

some republicans push back today and say, well, we'll have you back in open testimony so we can question you again in public. and i do think that this is going to be a theme going forward of, again, republicans trying to paint the dossier in a certain light and the people behind it as metical operatives. and this is going to be, i think, a little bit of the chess match going forward. >> sreenivasan: and, mark, as your team or teams of the reporters at the "new york times" uncovered as early as this last weekend, the dossier and what's in it is not the reason the f.b.i. launched the investigation into the russian meddling in the first place. >> as we reported over the weekend, the predicate for the investigation which began in july 2016 was not the dossier, it was a couple of things, and a significant factor in it was this meeting that george papadopoulos a former adviser to the trump campaign had a night of drinking with australia's top

diplomat in the kingdom in may of 2016 and revealed he learned russians had dirt on hillary clinton. a couple of months later his government cabled this government and led to the investigation being launched later that month. >> sreenivasan: robert costa, the president has had multiple statements on what he thinks about robert mueller, the f.b.i., the d.o.j. one of the most recent ones is he thinks robert mueller will be fair but this investigation makes the country look bad. how do we figure out what his threshold is for tolerating how close this investigation is getting and perhaps how that infuriates him? >> so far, the indictments that have come forward have been to campaign advisors to the president's campaign in 2016. they have not reached his inner circle in a major way. they have not reached his own

family or himself. and because of that, there's a reluctance among the president, i'm told, to really combat mueller at this time, to go after him in a public way. that's why he keeps saying, in statement after statement, that he believes mural will be fair and that he's just going to let the process play its course. but there's a spoiling right now on the right for a fight against mueller that this investigation has gone on too long. so if he ever changes his tune, the president knows on the right wing of the republican party, there are elements and groups and major figures who are telling him in the white house we are ready to take on mueller. we haven't reached that threshold yet, in part, my reporting tells me, because this investigation has not come exactly into the white house in a serious way the white house would see as debilitating. >> sreenivasan: robert costa, mark mazzetti, thank you both. >> thank you.

>> brangham: protests continued across iran today, watched closely by the white house and other global leaders. the demonstrations center on economic insecurity and a lack of opportunity, especially for the islamic republic's young people. now, the iranian government is moving to counter the message of the protests. after a week of growing national protests, the iranian regime sought to change the narrative. state tv showed tens of thousands of people marching in orchestrated, pro-government demonstrations. in markazi province, people held up signs supporting supreme leader ayatollah ali khamenei. but state media ignored cell- phone video of protesters tearing down likenesses of khamenei in noor-abad, 200 miles southwest of iran's capital tehran. crowds there also burned an ambulance, after accusing the local hospital of refusing to helping their wounded. supreme leader khamenei has blamed the protests on "enemies

of iran," and today, the commander of the elite revolutionary guard sent troops into three provinces to put down what he called "the new sedition." some in tehran urged the regime to heed legitimate concerns about the economic woes of the iranian people. >> ( translated ): protesters are divided into two groups. one group is really protesting, and the other is rioting. why should they arrest someone like me when i protest the rise in the price of eggs? >> ( trnslated ): if the protest slogans are insulting, nothing is going to be resolved. on the other hand, my husband and i are working together but still cannot make ends meet. >> brangham: from washington, president trump again tweeted his support for the protests, and he promised, "you will see great support from the united states at the appropriate time!" meanwhile, u.n. secretary general antónio guterres condemned the loss of life, and called for avoiding further violence, and turkish officials said iran's president hassan rouhani told turkey's president recip tayip erdogan that he hopes the unrest "will end in a

couple of days." for more on the latest in iran, i spoke earlier today with thomas erdbrink of the "new york times." he's in tehran and has been covering the protests for a week. thomas, you wrote today that the blossoming of these protests was really driven in large part by the leak of a governmental budget that showed big increases in money to clerics and hard liners and military groups at the same time as cutting money from social services for the iranian people. can you tell us a little bit more about that budget and why it struck such a chord? >> the presentation of iran's budget proposal every year is a big thing because it contains, you know, most financial information of the country, and this year the proposal was presented quietly, but when people started going through its pages, they found information they previously hadn't seen, information on iran's religious institutes, for instance,

information on the budget of certain parts of the revolutionary guards, information on the budgets for someone who was upkeeping the library of his deceased ayatollah father. all the information that showed that the government as part of its annual budget is forced to pay also to these institutions. now, at the same time, they also read in the budget that they would be forced to pay more for fuel. they read in the budget that the monthly cash handouts of iran, $12 a person, would be canceled for 30 million iranians. so putting those two pieces of information together was something that made a lot of people on iran social media at least pretty angry. >> sreenivasan: you also wrote these protests were a result of

miscalculation between more conservative hard line elements in the iranian government and what we might call more liberal reformers. can you explain a little bit of that? >> these two groups are constantly add outs with each other and recently have both tried to tap into the dissatisfaction over the bad economy. last thursday, a group of men without any prior announcement gathered in an eastern city and out of nowhere seemingly started shouting slogans about the economy, against president rouhani and even against iran's supreme leader, clips of these protests by hard liners were distributed rapidly across the country and pretty soon people followed suit and started making their own protests. seven case later, there have been protests in 80 different cities. so, yeah, you can say this was a miscalculation on the part of some people. >> sreenivasan: the revolutionary guard says they're

deploying to throw provinces and as reported president rouhani told the egyptians this would all be over in a couple of days. is this a sign of a crack down coming or do they think this will fizzle out? >> the head of the revolutionary job corps came out today and gave an interview to iranian media outlets and actually said -- stated that this sedition is over and he means the protests that have rocked this country in the past several days. the general wanted to give the signal that this was not happening in all the provinces. president rouhani has also been telling foreign visitors that the protests will also be over. >> sreenivasan: president trump again has signaled his protests for the protesters. are they hearing the support and how is it the support is being interpreted? >> we have been talking about social media, and president trump is very energetic on social media, so his messages do make it here

into iran, and while there might be a part of the protesters that are pleased with the support of mr. trump, there are, of course, a lot of people who remembered the long and difficult history between iran and the united states, and they might say that they are protesting for legitimate reasons, but that the support of mr. trump is making it harder for them to protest because it enables iranian hard liners to call for protests for an agent working for the americans, for instance. so it's not, let's say, a broad welcoming by all the protesters when they see these messages of support pl by mr. trump. >> brangham: thomas erdbrink of the "new york times." thank you so much. >> thank you.

>> brangham: we now turn to one of the president's favorite means of communication: twitter. and, how those messages are read around the world. the new year's tweet storm is the latest example of president trump using the medium to conduct foreign policy-- and this time, it runs the gamut. on saturday, he signaled support for anti-government protesters in iran, saying, "the entire world understands that the good people of iran want change." that provoked a rebuke from iranian president hassan rouhani: >> ( translated ): this guy in america who wants to sympathize with our people today has forgotten he had called iranian people "terrorists" a few months ago. >> brangham: on new year's day, the president took aim at pakistan, accusing it of harboring terrorists and threatening u.s. aid. he tweeted, "the united states has foolishly given pakistan more than $33 billion in aid

over the last 15 years, and they have given us nothing but lies and deceit." that incited protests in pakistan, with demonstrators burning american flags and chanting anti-u.s. slogans. north korean leader kim jong-un provoked another tweet, when he sounded this warning on new year's day. >> ( translated ): the entire united states is within range of our nuclear weapons, and a nuclear button is always on my desk. >> brangham: last night, mr. trump shot back that he has an even bigger nuclear button. and late yesterday, it was the palestinian's turn: the president warned the u.s. could cut off financial aid to the palestinian authority. his tweet said, "with the palestinians no longer willing to talk peace, why should we make any of these massive future payments to them?" palestinian officials across the political spectrum denounced the threat as blackmail. it's unclear if the president is seriously considering withholding aid to the palestinians, but this wouldn't be the first time his tweets have gotten ahead of official

policy decisions. critics in congress say his off- the-cuff pronouncements, turning complex issues into simplistic statements, are unsettling allies and encouraging enemies. >> president trump's foreign policy by tweet is doing serious damage to the country. where we have serious issues to address abroad, president trump seems happy with macho boasts and belligerent threats that get us nowhere. >> brangham: even so, press secretary sarah sanders today defended mr. trump's way of doing business. >> i don't think that it's taunting to stand up for the people of this country. i think what's dangerous is to ignore the continued threats. if the previous administration had done anything and dealt with north korea and dealt with iran, instead of sitting by and doing nothing, we wouldn't have to clean up their mess now. so, how is the president's unorthodox style of communicating heard in foreign nations? is it effective? ambassador nancy mceldowney was

a career foreign service officer, severing in a number of senior posts at the state department and on the national security council staff. she's now director of georgetown university's master of science in foreign service program. and, kenneth weinstein is the president and chief executive officer of hudson institute, a washington, d.c.-based think tank. he's written widely on international relations. welcome to you both. nancy mceldowney, i would like to start with you first. this is how the president likes to communicate, and he's communicated some substantive foreign policy messages. now, you can only pack so much into a tweet. i'm just curious, what do you make of this strategy? >> i think it's very problematic, and i'll tell you, when you look at the course of the president's tweets, they range from being disruptive to downright dangerous. on the content of the tweets, they're often impulsive, filled with more emotion than real strategic intent or any analysis. the process is often very difficult because it's in

conflict with aspects of the policy that are being implemented by other parts of the administration and then, most importantly, it's confusing to other world leaders who are often asking what is american policy, what's the long-term plan and how are we supposed to react when we don't know whether what comes out of the president's tweets is really what the united states stands for. >> brangham: kenneth weinstein, what's your take on this method of communication? >> the president views himself as being elected to bring disruption to u.s. foreign policy. he saw his election as a means to really shift the direction of policy, policy that he thought benefited america's elites and global elites at the cost of what the average american voter would have wanted, and he views his tweets as a means of communicating directly, frankly, both to americans and leaders abroad, first and foremost that president obama's era of strategic patience is over,

secondly that there's been a shift in terms of diplomatic speech, those days are gone, that there needs to be a real focus on policy and polesy direction and even in the tweets you cited just now, on the pakistani, the situation with regard to pakistan, that's been the president's policy almost since day one when he came in, the policy of the national security council which is to say pakistan cannot be trusted in the war on terror, we're shifting and pivoting towards india. toward congress, house has voted to cut back 80% too the palestinian authority. some of these statements are statements of policy that he -- and he is stating it very directly, bluntly and getting it around the world instantaneously without the filter of the u.s. main media which mas not been exactly the president's best friend bibb what do you make of this? kenneth is arguing it may be

blunt, it may be sort of a blunt tool to use, but he's communicating things he feels keeply and he wants u.s. policy to reflect. >> there's no question that the twreets do give us sort of a telescoped view into the president's psyche, his world view and emotional state. the problem is that it is often in direct conflict with the policy his administration is trying to implement and often doesn't correspond with the facts on the ground. so take, for example, the palestine issue, the reason that we are having difficulty in the peace process right now is because of the decision that president trump took on recognizing jerusalem as the capital of israel and moving our embassy there. >> brangham: that was not a tweet, it was a policy choice. >> that was a policy choice and whether you agree or disagree, that was the policy made but was not in consultation with any of our european allies or countries in the region. so, when you look at the impact, what happens after that, we have

universal condemnation of that decision. our perception, the perception of the united states by other countries has plummeted around the world, and when there's a vote at the united nations on this particular issue, over 100 countries vote against us. only nine vote with us. so we see an erratic, an impulsive quality to trump's tweets that, in some cases, may accurately reflect the policy of his administration. but, frankly, when you look at it and when other world leaders look at it, instead of a blunt statement of policy, they see a sort of brashness and a buffoonery that is not helping our country and, in fact, is leading us into further isolation. >> brangham: kenneth, i want to ask you specifically about north korea because, in this case, we have the president tweeting not so thinly veiled insults at the north korean leader, and he gives just as

good back to president trump in return, but we don't really know perceives things, how much he understands what the president might be saying and, at its core, we are talking about the possibility of thermonuclear war. does it not trouble you at all that the president seems to be engaging in a who's got the bigger nuclear button when the stakes could be incredibly serious? >> in april 2016 when barack obama was president, he called -- publicly called kim jong un erratic, said he was irresponsible and said that america's nuclear arsenal could "destroy his country," and those are direct quotes from barack obama. >> brangham: a little different than rocket man and calling him a child. >> he is erratic, irresponsible. what the president is trying to do is bring the attention of the north korean leader and others around the world that this is a serious problem, that the united states has to deal with this. he's working very closely with the japanese on this and sending

a very clear signal that there's not going to be room for mealia-mouthed negotiation that's going to let kim jong un walk awe way with his weapons at some point, and i'm not going to defend every one of the president's tweets, but this is an example where he's trying to send a very clear signal that we mean business when it comes to north korea and, furthermore, i think it's clear what the president is trying to do and it's putting pressure on kim jong un. >> brangham: kenneth weinstein, nancy mceldowney, thank you both for being here. >> brangham: stay with us. coming up on the newshour: what you should know about the new tax law. and, a special announcement from our team behind the "newshour bookshelf." but first, there's long been a big push to promote better dental health through fluoridation and telling people to eat less sugary foods. despite those efforts, tooth decay remains a major public

health issue. in fact, it's the most common chronic childhood disease, and 90% of all adults have cavities. as many of us know, traditional treatments can often be painful, but a new, pain-free, low-cost dental treatment could have a significant impact in time. special correspondent cat wise has the story, part of our breakthrough reporting for our weekly series about the "leading edge" of science and technology. >> reporter: it's an unmistakable, stomach-churning sound: the high pitched whir of the dentist's drill. for more than a century, it's been one of the main tools in the battle against tooth decay. the standard "drill-and-fill" treatment is not a lot of fun for anyone. but for some patients, especially young children who often have to be sedated or put under, it can be very challenging, and even dangerous. but the silvery liquid in this little bottle has started to

lead to some big changes recently in the way some tooth decay is being treated. >> we started in 2013 using this, and it's-- in 35 years, i have not seen anything that's worked as well. >> reporter: dr. frank mendoza is a pediatric dentist on the warm springs indian reservation in central oregon. he is one of a small but growing number of dentists who've begun using silver nitrate, a widely used liquid anti-microbial medical treatment with fluoride varnish, a widely-used dental product, to stop tooth decay. the treatment is for cavities in the early stages which haven't reached the pulp of the tooth. >> the silver kills the bacteria, and stops new bacteria from growing. the fluoride re-mineralizes, or hardens, what's left. that hardened material then can be used to-- you can actually bond or stick a lot of filling to material to that. >> reporter: on a recent morning, 13-month-old zavion wallulatum and his siblings paid a visit to dr. mendoza. zavion has eight teeth so far,

and despite his family's best efforts to keep them healthy, four have cavities. three months ago, dr. mendoza began the first of several treatments. the cavities have been stopped and, as of now, no new ones have formed. the black spots on his teeth are actually the silver doing its job on the decay. the staining is the main drawback of the treatment, which has been used in other countries, and which has been shown to be safe in studies. >> hi sylvia, let's see how you are doing. >> reporter: six-year-old sylvia is also getting treatments, and so far, her cavities are under control too. but older brother frederick, who developed cavities as a toddler psilver in his practice, ended p under general anesthesia in the hospital. that's a common story for young children in warm springs, and in tribal communities around the country, which have high rates of dental decay. >> over half of the kids went to

the hospital, up until we started this silver nitrate project four years ago. we've seen about half as many kids requiring o.r. treatment since then, and we've changed nothing other than add this to our program. >> reporter: the dark spots can eventually be covered with tooth-colored material, and when the baby teeth fall out, the stains go away too. mom nancy wallulatum says she doesn't like the stains, but she believes the treatment has kept her younger children from having more-invasive work done. >> it's really fast. you just come in and out and then we're done. i think it's really helping them to prevent them to not go to surgery. >> reporter: preventing kids from being put under, or sedated, has become a priority in the dental world. the authors of a recent article in the journal "pediatrics" wrote, "an estimated 100,000 to 250,000 pediatric dental sedations are performed annually in the u.s.," and they

highlighted the case of a four- year-old boy who died after sedation in his dentist's office. but, they noted it's difficult to track "adverse events or deaths" because there's no "mandated reporting." the article's authors joined an expanding group of dental experts, including the american academy of pediatric dentistry, who say a treatment that combines silver and fluoride can be effective, in appropriate cases. the formula, called silver diamine fluoride, or s.d.f., was cleared by the f.d.a. last year for reducing sensitivities in teeth, but its so-called "off-label" use for stopping cavities is now its main use. the treatment is much cheaper than drilling, typically about $30 per visit. some state medicaid plans and an increasing number of private insurance providers are now covering it. but a lot of questions remain, including why s.d.f. works only about 80% of the time. >> it works on most cavities. the problem is, it doesn't work on all cavities.

>> reporter: one of those on the frontlines of s.d.f. research is dr. jeremy horst, a pediatric dentist and post-doc fellow at the university of california san francisco. he and his colleagues are studying, among other things, the structural and chemical changes in teeth before and after they've been treated with silver products. >> we completed a short term study, which blew our minds. it didn't look like the bacteria changed very much at all, there were just dramatically less of them. so it decreased the infection dramatically. that was when it worked, so we need to look longer-term, and we need to look at cavities that didn't stop. are there certain bacteria that are making the infections, the cavity in the tooth, still grow? >> reporter: dr. horst is also studying how often silver products need to be reapplied to be effective, and he's using extremely high-res x-rays of treated teeth to uncover how the silver and fluoride, seen in red in this photo, work their magic. >> so this is a bit of a tooth we've imaged, so the dark area is the cavity. the surprising thing is, the

silver penetrates down into the inner part of the tooth. pretty well as far as the cavity goes, and sometimes beyond, and reinforces it and strengthens it. increases its hardness. >> reporter: and that's a good thing? >> that's a good thing. teeth should be hard. >> reporter: u.c.s.f. is teaching both pediatric and general dentistry students about s.d.f., but it's not universally taught, or practiced, around the country yet. there others though who could benefit if the treatment spread. 61-year-old keizer, oregon resident robert block had a stroke 12 years ago that made it difficult to care for himself and his teeth. dental decay is a problem for many older adults, especially those in nursing homes, where it can be tough to get dental care. block began getting silver treatments from a local dentist who was one of the first to try using silver more than a decade ago, dr. steve duffin. >> we just put silver compounds on all of his teeth, and i'll never forget, he came back three

months later, i looked in his mouth, and he had no plaque on his teeth. his gums were healthy. he looked like a different person. >> reporter: dr. duffin, who discovered in an old dental textbook that silver nitrate was actually used in this country for a time in the early 1900s, believes what was old is new again, for everyone. >> i personally believe that this is the appropriate treatment for every person who has tooth decay, because it is the most effective way to treat the disease regardless of income. >> reporter: in oregon, the treatment has been approved to be used by hygienists and qualified dental assistants, and dr. duffin says that could have a major impact on access to dental care. back in warm springs, dr. mendoza says prevention of cavities should always be the focus. but when needed, silver is making a difference. >> i won't ever go back to the same way of doing it. i don't think parents would allow me to, because they know

that there's another way to do it. it's not a silver bullet, it's not going to stop everything. you need follow-up and you need to start it early. >> reporter: later this year, the american dental association plans to release a clinical practice guideline on all non- surgical approaches to cavities, including s.d.f. for the pbs newshour, i'm cat wise in warm springs, oregon. >> brangham: 2018 is three days old, which means the republican tax reforms are now the law of the land. president trump signed the bill just before christmas, allowing the internal revenue service little more than a few days to make what amount to historic adjustments. lisa desjardins looks at how the agency is scrambling to get up to speed. >> desjardins: for that, i am joined by nina olson, the national taxpayer advocate at the i.r.s. it's her job to help taxpayers

understand our rights, and see that they are treated fairly when they file their taxes. thank you for being here. all right, so we have a lot to talk about with this new tax law, but first i want to take a deep breath and talk about the i.r.s. right now before the law. can you give us a clear picture of how able the i.r.s. is to handle the questions they face already? >> right now the i.r.s. is projecting, before the tax law, that it was only going to be able to answer six out of ten calls during the filing season from taxpayers calling to speak to somebody, and for the whole year they would only answer four out of ten. it gets about 100 million calls a year from taxpayers and, right now, it's already said it's not going to answer -- it hasn't been answering tax law questions after april 15th of each year. >> desjardins: what happens to those who don't get through is it. it --? >> they don't get an answer to their questions, maybe they have to go pay somebody to get an answer to the question rather than getting the information for free from the i.r.s. they can go to the i.r.s..gov

web site, it has 140,000 web pages, so do a search on that and see what comes up. >> desjardins: a bit daunting. it's a little daunting. >> desjardins: let's talk about this new tax law and, of course, there are many questions, already, do we have anything from history that tell us the response from taxpayers, the needs that taxpayers may have to such a change in the tax law? >> well, you know, there are a couple of instances. in the last major reform in 1986 the i.r.s. phone calls increased 14% in the year of that enactment in the filing of that year. they hired 1300 new employees. they expanded their call hours and things like that. they had to do about 131 new tax forms or revised forms and a whole bunch of new publications. with the 2008 economic stimulus payment, the phone calls where people got $300 or $600, the phone calls went from something

like 67 million to 151 million. it was an increase of 125%. >> desjardins: and that was a more simple change. >> you're getting money back. >> desjardins: let's talk about specifics, property taxes. >> yeah. >> desjardins: you may have seen thousands of americans last week lined up to pay their property taxes ahead of time hoping to get the deduction one last time before the law changes. the i.r.s. guidance on this came out but i'm not sure it was ironclad. do we know if those people will get the deduction or not? >> the i.r.s.'s position is unless your taxes have been assessed, your 2018 taxes were assessed in 2017, you won't get a deduction. some of the states have come out saying, well, this is a state's right issue, we get to decide whether they're assessed or not. some localities said we're not changing our assessment procedures and, by the way, we're not refunding. others have said we don't know

quite what we're doing. i'm worried going forward people might claim the deductions, maybe they will get tied up with the i.r.s. denying them, then you have court and court will say is it state law or federal rule? i don't know the answer to that. >> desjardins: the pass-throughs or small businesses that get this new deduction, how much work does the i.r.s. have to do now to set the exact guidelines on who gets that and what do people need to know who are considering it? >> well, the i.r.s. hasn't yet put out guidance about that. this is one thing about this bill is we have a very short time frame in which to get guidance out. and my caution to people is don't make business decisions like this, just purely for tax reasons, and becoming an s corporation really has legal implications and all sort of other implications in your life. another issue we see with this is a lot of people who are now

wage earners are thinking maybe i should become an independent contractor, but that means that you're going to be responsible for paying your estimated taxes, and if you get behind, you may end up paying money in penalties and interest to the i.r.s. for not making your payments timely that might offset that 20% deduction that you might get. so you really have to think these things through. >> desjardins: some advice and still not very clear answers on that. how about on people's paychecks, show me the money, when is everyone going to see the changes that affect people's paychecks? >> the i.r.s. estimates they will get the withholding tables and formulas done no later than the third week in january and then that means that the software companies and the employers and payroll companies will have to get that built into their systems. so we're sort of expecting maybe mid february people will start seeing that. then we have to create a w-4 form because there are no longer any personal exemptions. so you have to re-create that form so people can fill it in.

>> desjardins: we've only covered a few of the aspects of this bill. how worried are you? what is the sense of the i.r.s.? >> the i.r.s. estimated in the next two years it needs about $495 million to really do the implementation of tax reform, reprogramming 131 systems that are going to be impacted by this law and getting publications and guidance and forms out. the i.r.s. is pretty good about getting stuff done, but the problem is if they don't get additional funding, they're going to take money going to basic services to taxpayers and move it to implement this law, and that harms everybody. so i think people are worried. >> desjardins: no big deal, it's just the tax code. >> it's just the tax law. >> desjardins: nina olson, national taxpayer advocate. thank you for joining us. >> thank you for having me.

>> brangham: and finally, an exciting project here at the newshour, in collaboration with the "new york times:" a new book club for the new year. jeffrey brown tells us more. >> brown: it's my pleasure to announce a new book club we're calling "now read this." every month we feature a new book, fiction, history, memoir and much more and we'll invite you to read along to join us throughout the month for features about the book, its author and send in questions that you have for the author for an interview i'll conduct at the end of the month. we're very excited about it and this is special and new for us because this is a partnership between the "newshour" and the "new york times." with me is pamela paul, editor of the "new york times" book review, and joining us is my colleague at the "newshour" elizabeth flock to tell you more about the book club's many features. pamela, first of all, it's a pleasure to do this with you. share with the audience how we thought about picking books and

all. >> i think what's unique about this book club is it is two news organizations working together and the books we're choosing are not only chosen on the merit of the book themselves but also really selected because these are books that matter now, these are books that touch upon our times, issues that we think are important now, and books that will engage readers and viewers in a discussion. >> brown: questions i'm asked is how do you pick your stories and books. there is a little serendipity of the moment, but the kind of urgency that has to be on a news program, that's something important, and that the what we talked about when we thought about this. >> yeah, at the "new york times" book review, our criteria is a bit different in that it does come down to the book itself. but i think what's ther interesg here is this is a book club selection and there are certain kinds of books that work well for book clubs and in this case makes sense tore a book club driven by the news. >> brown: tell people what they will find, where they'll

find it and what features they will have. >> the best way to join the book club is through our facebook group "now read this." we want everyone to join together there and read and discuss the book in realtime with members of our staff and fellow readers and send in their questions even for the author and also we'll be posting so much there from discussion questions to help guide them as they read the book, to writers' advice from the author, to sort of an inside look at how the book was written. >> brown: all the tools you need whether you're in a book club or whether you want to start your own and follow us. >> we hope the book clubs around the country read along as we do. >do. >> brown: so that queues our first choice, jazzmond ward with one of the most acclaimed novels of the recent years. what interested you, pamela? >> it's a book itself which deals with race, violence, the

legacy of hurricane katrina, and it's also about the author and jesmond ward. this was our second naval book award. her second novel salvage the bones won an award in 2011. she won twice the national book award. she edit an anthology last year writers writing essays on race called "a fire this time" and wrote a memoir called "men we reaped" which was about the death of her brother and four other plaque men from mississippi. so much of her work is grounded in her community in mississippi. jesmond was the first member of her family to attend college. she went on to stanford and writes about the community she came from. one of the things i found most moving is at the national book awards ceremony this year when she accepted her award, she said she had been very discouraged

first by publishers who said they didn't think readers would be interested in reading about the kinds of people she wanted to write about. turns out she was wrong heavily on that point because readers have, in fact, been -- >> brown: yeah, because in this particular book, i'm cheating, because i got to read it months ago before a visit to the small town in mississippi. i want to show a clip of the interview we aired. news is jesmond ward talking a little bit about, in this book, turning to writing about the supernatural which was new for her and how it made her think about writing a little differently. let's take a look at that. >> most of my fiction is pretty realistic, right, and, so, here i was, you know, introducing the supernatural, introducing like the magical into my fiction, and it's a different kind of writing. it's tte kind of writing where you have to invent an entire world. it has to be believable. >> brown: tell us about what will people find with jesmond?

>> jesmond will give us some writers advice she received over time. one of the scenes is the oldest prison in mississippi, that long operated like a plantation, institutionalized racism for many years, and someone on our staff is doing a deep dive into the prison past and present. >> brown: at the end of the month i will interview you, jesmond, with questions you people will send to us and readers at the "new york times" and at that point we will also announce the next book which we three have been talking about and have an idea about and we'll invite people to send in suggestions for what we should turn to over the coming months. we hope this will build and build. we will have readers galore. for now elizabeth flock, pamela paul and all of you please join us for our new book club.

thanks. >> brangham: the white house announced late this evening it is dissolving the controversial commission having ting election fraud. a number of states had refused to share voter data with the commission. that's the "newshour" for tonight. thursday, on thursday, judy woodruff sits down with former vice president joe biden. i'm william brangham. join us online, and again here tomorrow evening. for all of us at the pbs newshour, thank you, and see you soon. >> major funding for the pbs newshour has been provided by: >> funding provided in part by 20th century fox. "the post," in theaters everywhere january 12. >> babbel. a language app that teaches real-life conversations in a new language. >> bnsf railway. >> supported by the rockefeller foundation. promoting the wellbeing of

humanity around the world, by building resilience and inclusive economies. more at www.rockefellerfoundation.org. >> and with the ongoing support of these institutions and individuals. >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. captioning sponsored by newshour productions, llc captioned by media access group at wgbh access.wgbh.org >> you're watching pbs.

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