captioning sponsored by newshour productions, llc >> woodruff: good evening, i'm judy woodruff. on the newshour tonight, northto korea threatenalk away. the regime cancels talks with the south and says i reconsider a historic summit with the u.s. in protest of int military exercises a tough s. demands. then, an inside look into trump tower-- the senate releases transcript of its interviews with the president's son and others about a controversial oneting with a russian lawyer and, our series junk news continues-- the battle inside facebook to combat theorpread of misition while keeping an open forum of ideas. >> we believe that we're not arbiters of truth and the people don't want us to be arbiters of truth. we also believe that censoring and fully removing information unless it violates our communitn standards the expectation

from our community. >> woodruff: all that and more on tonight's pbs newshour. >> major funding for the pbs newshour has been provided by: >> babbel. a language app that teaches real-life conversations in a new language, like spanish, french, german, italian, and more. babbel's 10-15 minute lessons are available as an app, or online. more information on babbel.com. >> supporting sos al entreprened their solutions to the world's most pressing problems-- skollfoundation.org.

>> the lemelson foundation. committed to improving lives through invention, in the ngs. and develoountries. 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 infmation at macfound.org >> and with the ongoing support of these institutions: >> this program was madee possible by rporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> woodruff: what seemed like a pretty g meeting between north korea's leader kim jung un and presidenm set for june 12th in singapore-- is now up in the air.no a toh korean official

released a statement late yesterday saying if the united states insists on complete nuclear disarmament, the north koreans are not interested in talking with mr. trump. >> we haven't seen aenthing. we hav't heard anything. we will see what happens. oodruff: president trump responded to north korean threats to cancel the june 12 summit with leader kim jong un if the u.s. ntinued to push pyongyang to abandon its nucle weapons. >> will you still inrist on denucltion in the korean peninsula? e yeah. >> woodruff: in e-dawn hours, pyongyang upset months of thawing relations. first, it abruptly suspended high level talks with seoul in protest of a joint u.s.-southa kolitary exercise called "max thunder." >> ( translated ): the south koreanuthorities, lost all senses, should be held wholly accountable for the scuttled north-south high-level talks and >> woodruff: the a warning for the u.s. about another

consequence of that annual drill: >> ( translated ): the united states will also have to undertake careful deliberations abe fate of the planned north korea-u.s. summit >> woodruff: hours later, state media carried a statement from north korea's first vice foreign minister kim kye gwan that rejected any notion of total he said, "if the u.s. is tryingu to driinto a corner to force our unilateral nuclear abandonment, we will no longer s be interested h dialogue before mr. trump spoke, press secretary sarah sanders said the white hoe is still "hopeful" the meeting will take place. >> look, this is something that we ful expected. the president is very used to and ready for tough negotiations and if they want to meet, we'll be ready and if they don't, that's okay, too. we'll continue with a campaign of maximum pressure if that is the case. >> woodruff: the north korean statement also criticized mr. trump's national security

adviser john bolton. last month, bolton invoked libya's 2003 disarmament as a model r north korea, and pushed for "irreversible dismantlement" before the lifting of sanctions. >> we have very much in mind the libya model from 2003, 2004. >> woodruff: thelibyan leader moammar gadhafi was overrown and killed in 2011 by rebels with u.s. backing. kim said it was an "awfully sinister move" to demand pyongyang do the same. at the white house, sanders seemed to back away fr bolton's comment. >> i am not aware that that's a model that we are using. look, again, this is thees ent trump model. >> woodruff: this follows, in the span of a few weeks, president trump shifti o from outrigimism. >> i think that we're gonna have a success. >> woodruff: to occasional caution. >> if it's not gonna be fair and reasonable and good i will,

unlike past administrations, i will leave the table. >> woodruff: for their part, china's president xi j ngping met with korea's ruling workers party officials and urged pyongyang not to cancel next month's summit. in the day's other news: president trump's choice tl lead the centtelligence agency, gina haspel, moved one stepma closer to confon. the senate intelligence mmittee voted 10 to 5 behind closed doors to approve her nomination. democratic senators mark warner and joe manchin added their support to the eight republicans already backing haspel. she's come under criticism for her role in the c.i.a.'s harsh interration techniques of terrorism suspects. a full senate vote coulascome as earlhis week. a new footnote has been added to president trump's financial disclosure report from last year. it's a reimbursement in an amount ranging from $100,000

to $250,000 for his personal lawyer, michael cohen. in the weeks before the 2016 election, cohen paid $130,000 td t film actress stephanie clifford, to keep her quietan aboulleged affair with mr. trump. the president denies the allegation. onesident trump modified his calls to ease sancagainst the chinese tech giant zte today. mr. trump tweeted on sunday that he'd ordered the commerce department to give tpany "a way to get back into business, fast." but today, mr. trump wrote that "nothing has happened with zte except ait pertains to the larger trade deal."r f.b.i. direcristopher wray told senators today that he's "deeply concerned" about the chinese company tining ground u.s. european council leader donald tusk had harsh words for

president trump today and his "capricious" policies. european leaders are scrambling to keep iran in the nuclear agreement, now that the u.s. has withdrawn. at an e.u. summit in bulgaria, tusk rebuffed warnings from the u.s., that it may sanction e.u. countries for dog business with iran. >> looking at the latest decisions of president trump, someone could even think, with friends likehat, who needs enemies?he as made us realize that if you need a helping hand, youin willone at the end of your arm. >> woodruff: iranian president hassan rouhani said today that tehran will not surrender to u.s. sanctions pressure. and an aide to ayatollah khamenei said he dous the deal can be salvaged. back in this country, secretary of state rex tillerson

had a stark warning for americans. tillerson delivered the commencement address today at the virginia milary institute in lexington. he said that the country faces a growing crisis in ethi and integrity. o if our leaders seek to conceal the trutwe as people become accepting of alternative realities at are no long grounded in facts, then we as american citizens are on a pathway to relinquishing our freedom. >> woodruff: president trump fired tillerson as secretary of state in march, after the two clashed over key foreignolicy issues the senate voted to preserve net neutrality rules today. three republicans joined democrats to pass the measure reviving the obama-era policy, aimed at maintaining equal access to the internet. the f.c.c. under president trump protections, saying they hamper innovation. the vote was largely symbolic, as the bill is expected to stall

in the house. the whistleblower who uncovered facebook's data-mining scandal warned congress today of a "new cold war" online.li christopher a former cambridg told a senate panel that the kfirm used people's faceb profiles to stoke paranoia and racial biases. the rm, which was employed b the trump presidential campaign, has annound plans to close. in north carolina, thousands of teachers flooded the state capital demanding better pay ang protesutbacks. educators marched through raleigh as the republican- controlled state legislature began its annuse session. clwere canceled in dozens of school districts. ikin several other states, west virginia and oklahoma, similar protests won teachers more funding. michigan state universs reached a $500 million settlement with the women and girls abused by former

gymnastics doctor larry nassar. over 300 of nassar's victims sued the university or failing to protect them. nassar is serving a decades-long prison sentence after pleading guilty to sexually assaulting patients while working at michigan state. and on wall street today, the dow jones industrial average gained 62 points to close at 24,769. the nasdaq rose 46 points. and the s&p 500 was up 11in . still to come on the newshour: what north korea is signaling ahead of a planned meeting with the u.s. ie key takeaways from a slew of documents releasn the russia investigation. on the ground in the war-torn retion of yemen, and much . >> woodruff: wreturn to the prospect of talks now in question between president trump

and kim jong un of north korea. for more on what the recent back and forth means, i'm joined by joel wit. he worked as part of the state department team that negotiated a nuclear agreement with korea during the clinton administration. he is now a senior fow at the u.s.-korea institute at johns hopkins university and founder of 38 north, a web site that focuseon korea. joel wit, thanucyou very welcome back to the program. how to you read what north korea n saying right now? >> well, there areber of different ways to read it, but i think the main way to read it is that, for months, we have been used to north korea essentially being a pussy cat, which is very different from the way they have been in the past, andh iink, now, they're reverting back to their past behavr in the rup to the summit, and that means trying to heighten the pressure on the united states to give a thood deal and by ehreatening to not go to th summit that's their attempt to

do that. >> woodruff: what prepitated this? can you tell what was behind these statement >> well, aside from the generalo h korean attempt to play tough guy, which they normally e could have been a number of other things that were going on. one, it may reflect dif sficults ret preparatory talks that are leading up to the summit t thatnk are being held in singapore. >> woodruff: and these have been underway. >> they have been underway because, as we all know, the leaders don't siin dowa summit and negotiate agreements by themsels. there's a lot of preparation ahead of time, so it could be a reflection of that. but, secondly, it's also a reaction to some of the statements by trump administration officials like john bolton which blyasicay to the north koreans you give up your nuclear weapons a then 'll reward you afterwards, and that's unacceptable to them. >> wdruff: so if bolton's

statement went too far, which as we record earlier the white house sounds like they're backing away, they're saying we n n't have a specific plr what we think north korea should do, but does sound as if there is room for the north koreans to do something, to do some step, some measure toward nuclear disarmament. >> well, that's exactly the case. that's what a negotiation is about. so what we're hearing, at least from the united states, we're hearing the openinh position, wh you give up everything, and then we'll give yo something in return, and the north korean position, which misn't public, but pretty sure is, no, we'll gradually give up things, but you give us things in return during that process. so the issue is whether the two sides can meet somewhere in between that's acceptable to both. >> woodruff: so the trump administration -- the north koreans are saying you need thi do som about these

joint exercises the u.s. and south korea -- they're saying a couple of things. the trump administration has been saying we're not going to make anyoncessions, it's entirely up to the north, but, in fact, are there steps that the u.s. and south korea ar going to need to take, to need to seriously consider taking before there can be any deal? >> well, there are a lot ofw steps becausat the north koreans are going to demand are, first, the normalization of relations with the united states, the tablishment of diplomatic relations. secondly, they're going to demand lifting of the sanctions. the third step they're going to demand is a peace treaty. a all of thee big steps for the united states and south korea to take, and issue is whether we're willing to do that and get denuclearization in return. >> woodruff: are you -- were you, before these statements happened in the last few days -- or 24 hou from north korea, did you have a sense things were

moving in a positive direction?u >>now, it's very difficult to say because most of us can only see what's going on in public, and there wasn't much going on at all except the occasional public statements by the north koreans and the united states. so it's hard to say whether things are moving in the right direction, and this could be the first sign things aren't moving in the right direction, and, so, we need to watch very closely and see whatw happens from to the summit. >> woodruff: what do you expect to happen next? t who make next move? >> you kow, i'm no sure there are any more moves yet because the secret talks are underway. we'll see what happens in those. there could be more back and forth publicly, but if we don't see an escalation of the current exchanges between president trump and thert koreans, then that means things are moving along in the ght direction. >> woodruff: do you have a gut instinct, joel wit, abisout whether ets back on track

or not? >> you know, all along i've thought there would be a summit, and a lot of people have been very skeptical abut that, and my analysis is from the north korean angle. iousink they are very ser about having a meeting with president trump and finding a way from conontation to a peaceful path forward. the issue is, as i said earlier, whether we can make the two sides' positions come togethe in a way that's acceptable to both. >> woodruff: joel wit with theor u.s.-k institute at johns hopkins university. thank you. >> thank you. >> woodruff: tomorrow marks one wayear since robert muelle named special counsel to investigate if the tmp campaign coordinated with russia's attempts to sway the 2016 ection.

trump lawyer rudy giuliani told the "newshour" that mueller said he will follow department of justice policy not to indet a sitting sident, but the mueller investigation continues, and it is not thel ony investigation into russia and trump campaign ac nick schifrin begins with new documents released today about a pivotal moment. >> schifrin: it was an undisclosed meeting in trump tower between donald trump jr., jared kushner, then gn manager paul manafort and a curious guest: russian lawyer natalia veselnitskaya. and today, the senate judiciaryt coe released thousands of pages of documents providing the most comprehensive look at that meeting. it was set up by rob goldstone, a british music publicist. goldstone had emailed trump panior he had dirt on hillary clinton that was of russia and its government's support for ju. trump" trumor replied, "if it's what you say, i love it." and he later told the committee, "i had no way of assessing where it came from, but i was willing to listen," and expected

incriminating information. the same day trump junior set up the meeting, his father promised tito soon reveal new reves: >> we're going to be discussing all of the things that hav taken place with the clintns. i think you're going to find it very informative and very, very inresting. >> schifrin: but trump junior told the committee he 't inform his father about the meeting "because i wouldn't bring him anything that's unsubstantiated... before i knew what it was actually about myself." he said the same last summer and called the meeting a waste of time. >> it was such a nothing. there was nothing to t i mean, i wouldn't have remembered it until you start scouring through the stuff. it was-- it was literally just a wasted 20 minutes, which was a shame. >> schifrin: last summer, when the meeting was first revealed, trump junior released a statement that initially concealed the meeting's purpose. asked by the committee whether president trump helped edit the statement, trump junior said thh president "me commented through hope hicks," the then communications director.to y's revelations come one

year after rapid fire, dramatice politicavelopments. james comey was fired as f.b.i. director. two days later, president trump said he'd fired comey because of ie russia investigation. >> and in fact, whecided to just do it, i said to myself, i said, you know, this russia thing with trump and russia is a made-up story. excuse by the democrats for having lost an election that they should've won. >> schifrin: less than a week later, one year ago tomorrow, robert mueller was named special counsel. and that brings us to today, when the senatmmintelligence tee confirmed the intelligence community's january 2017 conclusion that russia tried to tip the ele tion for donamp. that refuted the house intelligence report that accused the intelligence community of "significant intelligence tradecraft failings." here to unpack where the investigation stands, and what questions still remain, i'm joined by garrett graff, author of the book, "the threat matrix: inside robert mueller's f.b.i. and the war on global terror." and matt olsen, he's a former

federal prosecutor who directed the national counterterrorisre center underdent obama. welcome to you both. thank you very much. >> thanks, nick. >> schifrin: this is going on year two m of robeeller's investigation. the president says robert mueller has exceeded his remeant. has he and why han't we seen more conclusions. >> i don't think the special counsel has exceeded the remit scope of the investigation. if you look back at the document that set this in motion, the department of justice authorized the special counsel to look at anything linked to the russia meddling in our election andar mattersing out of that investigation. so it's a broad scope in fact addition, if you see what the special counsel has ne, he ha gone to the district of virginia, the judge there has approved the manafort

investigation, and he's als ferred matters out to other prosecutors' offices such as the investigation that's now new york against michael cohen >> schifrin: garrett graff there are a lot of aspects to this investigation. does robert eller embrace the kind of unwieldily notion of this investigation, or did heg expect somethch more narrow? >> well, i think what we do sees as matt said,ll of this falls pretty clearly under one big umbt lla and thamueller is being pretty careful trying to keep eunerythinr the umbrella. that said, what is clee is there number of different arms to have the investigation or sort of aspects of the probe. you have information influence operations. you have active cyber penetrations. you have money laundering and you have these suspicious russian campaign contacts as well as, of course, the big one that we're all wondering about which is the president's obstruction of justice. >> schifrin: so matt olsen,

let's go through each of those individually.d, as you've sahere's a specific language mueller was given which is investigate any links of coordination president trump and the russian effort to influence the election. the present says this is a witch hunt and there's no "collusion." do we know that yet? >> you know, i don't think we know yet. there is certainly, from my perspective, is evidence of collusion or what you would consider to be coordinationru between the campaign and russia. it's not hard to find that. you go back to the famed trump tower meeting in theu smmer of june -- summer of 2016. i there's cleardications of coordination between the trump campaign and rusia and their interference in our election. what we do knw, i think, is that the mueller investhgation, that team knows a lot that we don't know, and i say thatus be you know, they've got 100 charges pending, they've

charged 19 different individual and three individuals are cooperating, including michael flynn and george papadopoulos, people connected t the capaign. so there is a lot of information that the mueller team knows that we don't know yet. >> schifrin: among those inedated, garrett graff, a former campaign chairman paul manafort, rick gates pleaded guilty. s a different aspect of the investigation, it's about financial issues. it's about lobbying and anti-corruption laws. so how important is that part of this investigation to the overall investigation? >> we don't really know yet ad that's part of what makes this so interesting at this moment in the investigation. as matt said, you know, we just don't know how all these pieces fit together right now. we see a lot of pieces on the table. we see some money laundering, we see some coordination, we see some active cyberattacks and

information operatio don't really know how they connect. you know, how does the moneyl laundering rate to wikileaks? w does it relate possibly to s at trump tower meeting? and thaere, again, we think bob mueller is very far ahead of our public understanding. remember we're just learning now about the at&t and nopavartis ents to michael cohen through an essential consultants l.l.c., bob mueller knew that information in movent i think it's probably fair in all aspects of the investigation bob mueller is four to six months ahead of the public unsrstanding. >>ifrin: i want to show a tweet that president trump put out infending himself. he says the russia witch hunt rapidly losing credibility. how about obstruction? there is no capital ost ction. the president is fighting back. if the president is fighting

back can that b obstruction? >> obstruction can be fighting back. obstruction is corruptly trying to interfere and impede ain cr investigation. so you can go back, for example, the statement that the premasidt , according to jim comey, about michael flynn, let this go, t this thing against flynn. go that certainly isvidence of obstruction. what we don't know is what was the intent of the president in making those statements. was there corru intent behind that. that's something usually proved by the circumstances surrounding a statemt like tha also just the firing of comey himself could be viewed as an effort to obsucthe president's statement, part of the russia probe. those are the things i would be looking at to show evidence of obstruction. >> schifrin: garrett graff, matt olsen, thank you very much to both of you. >> thanks.

my pleasure. >> woodruff: the impoverished nation of yemen stands on the brink of collapse, with e worst humanitarian crisis in the world. three quarters of its 29 million people need humanitarian assistance. there are 1 million suspected cases of cholera. and 10,000 people have died in a brutal, three ilyear old car causing all the misery. o side of the war: shiite houthi rebels, a religious minority in yemen, backed by iran, who now control thea, capital, sannd the second largest port city, hodeidah. on the other side: t government forces of president abdrabbuh mansur hadi, and a coalition led by saudi arabia, ich includes the united arab emirates and the united states. a saudi-led air campaign has pounded houthi strongholds in the north, and cut off aid and

food, driving many people south, homeless in their own land tonight, with the support of the pulitzer center on crisis reporting, special correspondent marcia biggs reports. >> reporter: it's being called the forgotten war. in yemen, a country where access for journalists is limited and dangerous, the world's worst humanitarian crisis goes largely ignored. but after months of waiting, we were able to get permission toth entecountry through the southern city of aden, which is the new de-facto capital ofrn yemen's gont, controlled by the saudi led coalition. we were hoping to get areas under siege, but kept hitting a wall. it's incredibly difficult to access the northern houthi controlled areas to cover what's going on theca. even if yosecure permission from the houthis it's getting there that's the a oblem. the airport in san shut. there is one flight from djbouti for humanitarian staff, but the

saudis control who gets on that plane, and they're not giving permission to american journalis right now. you could drive, but it's a journey that used to take six no guarantee that you'll actually reach the destination, that you won't get turned around half way, half way there so we went to a village called basateen, on the outskirts of aden, to try to tell the story as best we could. so since we can't get to the north to the houthi controlled areas wee going to talk to some people that have recently arrived to find out what life is like there. living in this one room are t souad, h sons, and daughter-in-law. souad says she fled dail airstrikes near her home in hodeidah one month ago, but the thck of food was worse tha bombs. >> ( translated ): life is diicult there. people are hungry. they are looking for water, g forng for food, look work, but there is nothing. we would eat once a day.ea if we had brast, that's it for the day. if we had lunch, that's it forth day. >> reporter: lots of diseases have spread there. children are getting malaria, their platelets are low.

they are very sick because of. lack of fo areas here in the soedh are "liberfrom houthis and far from the front line. people may be safe from the fighting, but they still face the daily threat of starvation. so here inden, it's a big city, food is available. the problem, the prices.we poke to one shopkeeper who told me that a bag of flour three monthsgo cost $10, now it costs 17. but souad is living outside of e en, where food and money are even harder to com. she says her son makes around $3 a day as a laborer, but work is sporadic. when they have money, food is the first thing they try to find. so there are some vegetables. fi lahem? no meat. fi hubuz? no bread. fi fiz? no rice either. just the vegetabs. who do you blame? >> ( translated ): god help us with this situation. we don't know who caused it or who to blame.

they are both fighting, i don't know. >> reporter: yemen was already the poorest country in the middle east before the war. in 2015, houthi rebels, supported by iran, captured huge areas of the country, and the existing government made a deal with saudi arabia to fight the houthis, driving them back north, where saudi arabia and a coalition which includes the united states has pounded the houthis with bombs and tried toh chokr supplies with a blockade. amid international outrage, some u.s. lawmakers have sought to stop the fw of money and weapons to saudi arabia. but the trump administration recently approved a deal to sell the saudis $1.3 billioh of weapons. ahmed bin ahmed al maysary is yemen's interior minister, a cabinet member of battled and exiled president abdo rabbo mansour hadi. how does it make you feel that yemeni people in the nth are being bombed, starved in the name of fighting houthis?

>> ( translated ): is there a war in the world were people don't die? war is a disaster on all levels. we didn't start this war, we they came supported by iran to takeover our identity an doctrine that we had since 1400 years. w wh is imposed on you, you have to fight back.r: >> reporte but the cost of that fight is high. y to set up home as best as they can in the circumstance. you can see it close hangith on line. people are using these plastic sheets, too, for a sense of privacy. shabia mantoo is with the united nations refugee agency.>> n the past three months alone, we've seen more than a 100,000 people have to flee their homes. >> reporter: this former community center outside of aden is now a home for displaced yemenis and 33 families are crammed in this bustding, having rrived from the front line.at >> ( tran ): missiles hit our house in khokha, our house was totally destroyed. the bathroom was the only place left standing.

>> reporter: 17-year-old roseila fled with her two ely aunts, with only the clothes on their backs; they had to leave her mother and father behind. >> ( translated ): i'm very worried about them and i call them whei can. if we find something, at l mst if we findtresses, we will stay. >> you're not just dealing with the displacement, we're also dealing with an active conflict zone. it makes getting assistance to them quite challenging. >> reporter: you're struggling to keeup? >> yeah, definitely. i mean if you look at the numbers, 22 million people in need and humanitarian assistance is only fini, it requires more than humanitarian solution. it's caused by political problem and the solution to that is peace. >> reporr: 27-year-old elsam is the wife of a fisherman from yemen's western coast. >> ( translated ): we ate once a day. we were under siege, we could not get anything. all we had was what we could catch in the sea. >> reporter: but they are now0 liviles inland, so supporting the family is difficult, especially with a daughter copg with epilepsy. >> ( translated ): we have to

drive two hours to bring her seizure medicine. it's not available around here. we try our bt to provide the medicine for her every ten days, but it's very expensive. reporter: for those most vulnerable it's hardship after hardship.ha yemehistorically imported 90% of its food. so restrictions on imp are a huge blow. fuel shortages, inflation, anden rising unemploare crippling the country. we're dealing with a situationou in yemen wheree got functioning state services that that are now on the brink of collapse the health system is families are struggling to make the choice of deciding which meild to feed, which child to send to hospital, these are really heartbreaking decisions, but this is what life is like for civilians now impacted by war in yemen. >> reporter: here in this small regional hospital in lahjor province, just of aden, dr. marwa gamal says she sees around a dozen children per month with severe acute malnut complications.hem with 10-month-old mohamed was already

malnourished when he contracted measles and bronchopneumonia. his mother said when she brought him in she thought he was dyin"" his eyes were closed and he wasn't breathi," she says. is the biggest problem malnutrition or disease? >> disease. >> ( translated ): malnutrition is controllable if there are no complications. but when they come withs diseases, thisch worse. there are cases that died. we could not help them becauseom theytoo late. they die because of complications. >> reporter: like many public sector employees, dr. gamel continues to work despite an intermittent salary.at >> ( tran ): i love my work. this hospital is in my village. if i don't h own people, who am i going to help? >> reporter: are you concerned about what will happen when they leave? >> ( translated ): yes of course. i'm worried that the children will get worse or get sick again if the parents don follow the proper course of treatment. >> reporter: a cycle of displacement, malnutrition and disease brought on not by famine

or natural disaster, but by man. is there a point when you willno say,h. yemeni people are suffering, being bombed and starved, wefi have t another way? >> ( translated ): wartiill not end it's mission ends, and in the past three years we paid a lot. there is still little bit left to pay and it has to be paid, so the bill is completed and the mission done. the blood we lost can't go for nothing, but to let this blood go in vain and surrender, means we've neither achieved the mission nor saved lives. they should have not staweed it. but noe on this journey and we have to finish it.ep >>ter: we were poor before the war, one woman told me, but the war just finished us. for the pbs newshour, i'm marcia biggs in aden and lahj provinces, yemen.

>> woodruff: voters in four states went to the py ls yester pick republican and democratic nominees ahead ofte rtvember's m election. lisa desjardins reon the >> desjardins: last night's primaries anned the country and the political spectrum, from more liberal oregon, to conservative idaho and nebraska to swing state pennsylvania. and a clear theme: wins by women in competitive congressional races, from environmentalne pljamie mcleod-skinner in oregon to nebraska and nonprofiv execkara eastman, who pulled off an upset over a more moderate democrat. nowhere felt the so-called pink wave more than pennsylvania, which currently has no women in congress. that will change next year. last night one republican and wven democratic women wom their primaries, setting up onee race both candidates are women. among the pennsylvania winners,

democrat susan wild, the progressive solicitor of allentown. >> this isn't just for me. this isn't just for the next generation. this is for women who have been waiting a long time to have an equal voice in our government and i want to be part of the group that does that. >> desjardins: to take a closer look at the results, i'm joined by dave davies. he's a senior reporter at pbsst ion whyy in philadelphia. dave, let me ask you, you have been covering politics for 30 w yeart did primary voters tell us last night? >> i think in pennsylvania theye told us ty're ready for a change, but the biggest changes, really, lisa, are the changes in the playg field in pennsylvania. if you're looking in the philly pene, three things hap one, there is a surge of activity among progressive democrat a lot of them women who ran for offers and contributed to candidates. second, this isa seismic shift, eme court retrue all of the congressional boundaries, regarded them as

gerrymanderein favor of republicans and the new boundaries drawn by a court of justices largely elected as democrs in partisan races created districts more favorablc to demts. third thing, up three republicans represent decided not to run again, so you had more democrat-friendly districts and republican incumbents. that was attractive to a lot of democratic women, in particular, and at a got in and really performed yesterday >> desjardins: trying to get to a national summary here, democrats are hoping t those open seats in pennsylvania are one of the waythey're going to take over the house. but yet if more progressive candidates as we saw last ght are winning, what is your take? are those protegressive candi more or less likely to help democrats in the fall? >> well, i think because thee seats have rearranged, i think at least three of the progressive democrats who won yesterday are very liky to win their elections in the fall and that would rest in a net gain

of two seats for the pennsylvania delegation, fr the democrats. i think they have a very real shot at three more, and that could mean th pennsylvania could contribute five seats to s pretty good heart for the democrats to try to retake the house. >> desjardins: also conservative republican lou baretta in the senate race won that republican primary.yo what dmake of the dynamics there? how much is president trump going to be a finctohe democratic senate race. >> he will be a factor. lou baletta a congressman from pennsylvania championed on cracking down on immigrants. in congress he is among terrelliest and most vocal suppor.rs of president tru so president trump is going to be a big factor in that race, nt what happens. barletta will take on a o-term incumbent, bob casey, a democrat, who is not exexactly mrtement but comes from a well-known family name, so i

bigk trump's going to be a issue in that race in the fall. >>esjardins: six mons to go. you have a very interesting state and interesting midterm election nationally. we'll keep checking back with you. iave davies of whyy. we'll get backth you. >> good to be with you. >> woodruff: facebook is under pressure to crack down on falses fake accounts and inflammato manipulated to influence the public. this week, the social media giant announced it deleted 865 million posts in the first three months of this year. most of it was spam. the company also quickly di billion fake accounts but that isn't everything. tonight, we take a look at how facebook tries to tackle the content it won't delete. miles o'ien has been examining the problem of junk news and his last report in a speci

s e "newshour" has worked with facebook on proje the past. this is the last report in a special series as part of our weekly look at the leading edge of science and technology. >> reporter: inside facebook i headquarn silicon valley, they are trying rethink the" column of babel" that the newsfeed has become. >> so, i don think this is actually necessarily all that bad of a design even though it doesn't look that great. >> reporter: here they are trying to figure out how rate the quality of the news we like and share. more clearly identify the source. crfer users some context. and make sure the m rises to the top of the feed, while the junk sits at the bottom. >> we don't want a false story to g distribution, so we demote it. >> rorter: tessa lyons is product manager of newsfeed integrity. she works with two competing goals in mind: keep the platform free and open to a broad spectrum of ideas and opinions and reduce the spread of

misinformation. why not just delete it? >> well, it's an interesting question and i think, look there's real tension here. we believe that we're not arbiters of uth and the people don't want us to be arbiters of truth. we also believe thfu censoring any removing information unless it violates our community stanrds is not the expectati from our community. so we work to reduce the damage that it can do and ensure that when it is seen, it's surrounded by additional context. >> reporter: even thourly half of all americans get their news from facebook, ste company init is a technology enterprise-- not ithe business of making editorial judgments. so they are outsourcing the work. the most clear-cut problem: content that is demonstrably false. to grapple with that they have turned to a 23rd-party fact checkers globally, including one of the internet's original arbiters of ct from fiction, snopes.com. we caught up witmanaging

editor brooke binkowski, a former newspaper and radio reporter, she works at home or at a neighborhood coffee shop in san diego. and this is a typical day? >> yeah. >> reporter:, usy day? yeay. >> this is busier than normal day. >> reporter: facebook reacped out to sto be among itsck outside fact cs in 2016. >> it's gone from probably eight-hour days for us to more like, 12-, 15-hour days now e cause there's just so much to tackle and we all ue believerbasically. we all think that it's impoant, what we're doing. >> reporter: facebook says when a story is debunked by fact checkers ty reduce its reach by 80%.bi buowski remains skeptical. >> i still am not convincethat it's making a huge difference. >> reporter: part of the problem: old-fashioned shoe- leather reporting-- making calls to sources, doing the research, ipsometimes even taking a o a real library, takes time. >>atark twain famously said a lie can travel halfway around

the world while the truth is still putting on its shoes. i think it's gotn so bad now that a lie can travel like three times around the world, completely change, aects the perspectives and the votes of thousands of people and wreak havoc all over the place while the truth is still kind of getting out of bed. it's just happened much faster and it's overwhelming. >> reporter: at facebook they are keenly aware of this, but they see no easy fix, either from humans or machines. is it possible to match the rat at whople use the product? >> if we're always waiting for individual facts to be reviewed, that's going to be slow in each case. but by working with the fact checkers if we're able to understand the pages, the domains who repeatedly spread upstream to >> reporter: they are also looking upream for spammers bo create content that it is

factually correct, misleading, incomplete or polarizing, often called clickbait. to try and defenagainst this, facebook is using an artificial intelligence techniq calledar machine lening classification. the idea: feed the computer reams of clickbait examples, so that it can find patterns d learn how to spot this material and send it to the bottom of the newsfeed. so, with artificial intelligence, you can make the bagorithm smart enough to identify what isit from the spammer? >> this is using a machine c test help us scale this problem beuse two billion people, want to ensure that our solutions don't require individual manual review, but rather they can scale acss the platform. >> reporter: producer cameron hickey has been developing hisen own tool to idfy the junk as part of our reporting. in doing so, he has seen the limits of machine learning and the persistence of the adversary. >> using software to recognize patterns and then do something based on those patterns that you

recognize is only as good as the pattern remaining consistent. and the whole point of this problem is that the people who are trying to publish content like this, they're adaptive, so as soon as you shutdown one avenue, they move to another avenue. >> reporter: historicaunk news producers have taken advantage of the fact that most everything thaappears in the facebook newsfeed looks the same, whher it's heavily researched and vetted journali or pure junk. in the days when we bought newspapers and magazines at newsstands or supermarkets, iter was eao identify the difference between quality a junk. facebook is deveping ways to give its users some clues, in labs like this one. is>> what's going to happe that there's going to be red dots that pop up on the screyo. i just wanto follow them with your eyes. >> reporter: grace jackson is ae quantitaser experience researcher at facebook. she is showing m eye movements as a user reads a newsfeed.

she's testing to see how easily i recognize visual cues that an article has been fact checked or links are added for context.ew i y it. i think you need a little more there. >> this was our original design that we had tested and learned that a lot of people skipped right over it and never saw the entry point over here. >> well it's not obvious that's a click point, right? >> exactly, yeah. reporter: the eye tracking data helps product designermi jeff sth as he ponders new ways to give users clues about the credibility of information. >> we're in this new space and age where we're trying to desigs for new mech that people those credibility cues that used to be there via the publisher on the supermarket aisle or the newsstand. >> reporter: he's workon a design that more clearly identifi articles that have been debunked, provides context, related articles, and information abouthe publisher. >> i'm trying to give the users as much information as possible in a way that they can easily

digest and understand without getting in the way. k>> reporter: the faceboo newsfeed algorithm is finely tuned to hold our attention, originally without an emphasis on the quality of the content. but the company says it is trying to change that. >> we want to make sure that the news people see is high quality and we didn't have t.t stance befo and so, it's a pretty radical departure in terms of the way eaat we've been thinking about news and i think ay worthwhile one. >> reporter: alex hardiman is the director of products for news. she is leading facebook's effort to identify news sources that are credible, trustworthy and authentic. they're turning to their users thr the answer: asking them to rate news sources ey trust, and feeding those rankings into the newsfeed algorithm to determine what sources should rise to the top. with so many people getting their news from facebook, why don't you have a newsroom? >> because for us, thinking

through what quality means doesn't require us to have a newsroom. we're really trying to make sure at we pull in great information from publiand from the people who use facebook to make these decisions. >>eporter: but if given th choice, will users of facebook choose qlity over junk? the hyperpartisan content publisher we found in california, cyrus massoumi, is skeptical. >> they aren't "new rk times" readers necessarily. maybe some of them are butthhe majority o just want a 250 to 350 word article which will get them a little bit fired up. >> reporter: and the numbers back him up. his "truth examiner" page has 3.8 million fans, an stories he publishes generate a much higher rate of likes and shares thathe "new york times" and the "washington post." >> nobody wants to read that stuff when they're own their phone which is what everybody'st doing why're on facebook. like nobody pulls out their phone like and goes like, "aha! i'd love to read this 5,000-word

profile of like the endangered giraffe in like the congo." >> reporter: as long as user continue like and share junk news, should facebook redefine its role as a publisher? >> i think that they really toed ome to terms with the fact that they are a media company on top of everything else becauseno righthey keep saying they're tech, they're tech, they're tech. they're trying to avoid it allin coming cradown when they finally say, "we're media," because then, all those questions will come, "well, why didn't you do this? why didn't you do it that way? why didn't you listen to this? >> is it time for the company to take a little more responsibility about what is on th the newsfeed, what is o trending stories, in an active editorial way? >> i say, absolutely y responsibili, the tactics as to whether or not active editorial way, i would say we don't know. the first part, yes, we have a responsibility to making sure that the news people iee on facebohigh quality. >> reporter: the problem is far from solved, and the 2018 midterm elections are looming. even as the political races heat

up, here at, facebook they're running their own race, with no finish line in sight. i'm miles o'brien for the pbs newshour in menlo park, california >> woodruff: and you can watch all the stories in our series about junk news online at pbs.org/newshour. >> woodruff: now to our newshour shares. something interesting that caught our eye. yanny versus laurel. it's the auditory debate taking the internet by storm. newshour's nsikan akpan and julia griffin explain how one sound can create two different experiences. (sound playing) >> the internet has been set ablaze over one sound and two

wordau >> laurel, ll, laurel. so >> which did you hear? yanny or laurel? this audio clip, which first went viral oreddit and then twitter, features a robotic voice saying a specific word, but people's perceptions of that word differ dramatically. even in the newshour oice. how is it possible people are hearing different things? the sound is what's called an ambiguity illusion, and it's nothing new to neuroscientists. >> remember the dress from 2015? some people swore it was gold and white, others, black and blue. that viral photo is a visual version of an ambiguity illusion. >> when a human brain encounters something it can't immediately understand, it tries to fill in the gaps. >> in the case of yanny v. laurel, the frequency, or pitch, of the sound clip is cryptic to our minds. the original poster of the audio clip, 18-year-old reddit user from lawrenceville, georgia, recorded the pronunciation of "laurel" off dictionary.com rough his speakers.

that distorted the sound. this muddled sound causes our brains to fall back on theirna ral preferences. folks who prefer lowerie frequehear "laurel" while those who lean toward high frequencies hear "yanny." this might explain why children are reportedly hearing yanny. the human ability to hear higher frequencies fades with age. your speakers or headphones may also be to blame, as some sound systems are tuned to emphasize dierent frequencies. people discussing the sound can also shi your mind's perception. >> ambiguity illusions typically dcause our perceptions to one way or the other, but yanny- laurel and the dress stand out because they clearly split a room. >> but the neurological basis for exactly why is still ati mystery to scis.fo the pbs newshour, i'm julia griffin. >> and i'm nsikan akpan. >> woodruff: andhat's the newshour for tonight. i'm judy woodruff.

join us online and again here tomorrow eveng. for all of us at the pbs newshour, thank you and see you soon. >> major fundingor the pbs newshour has been provided by: >> consumer cellular believes that wireless plans should reflect the amount of talk, text and data that you use. we offer a variety of no- contract wireless plans for peop little, a lot, or anything in between. to learn more, go to consumercellular.tv >> babbel.a nguage app that teaches real-life conversations in a new language. th >> and witongoing support of these institutions and individuals.

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