captioning sponsored by newshour productions, llc >> woodruff: good evening, i'm judy woodruff. >> ifill: and i'm gwen ifill. on the newshour tonight, what we've learned so far about yesterday's mass shooting inç california that lef( 14 dead. >> ifill: also ahead ts thursday: we talk with the secretary of defense about his historic order to open up combat roles to women. >> woodruff: and, our special series, nigeria pain and promise continues. tonight, how gay people there face horrific abuse. >> i get calls. i get text messages. i get emails. threatening my life, that, if you don't stop what you'reçç doing, as an activist, as a gay activist, then, we'll kill you. >> ifill: all that and more on tonight's pbs newshour.

>> major funding for the pbs newshour has been provided by: ç >> and by the alfred p. sloan foundation. supporting science, technology, and improved economic performance and financial literacy in the 21st century. ç >> and with the ongoing support nstitutions 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. >> woodruff: there's much moreç today on the attacke$] and their weapons in the san bernardino shootings. but police and federal agents are still searching for what sparked the attack that killed 14 people, wounded 21 and culminated in a fatal confrontation. hari sreenivasan reports from san bernardino. >> sreenivasan: this morning, a bullet-riddled s.u.v. still sat in a san bernardino street, stark evidence of wednesday's violence.ç the fwo suspects, syed farook and his wife, tashfeen malik, died there in a gun battle with police, after a chase. hours earlier, the pair opened fire at a social services center during a holiday luncheon. police swarmed in to track the husband-and-wife team, ending in the final shootout a few miles

away. police chief jarrod burguan says the couple had an arsenal in the s.u.v., including two rifles and two handguns -- all legally purchased -- and bullets that could punch through police >> suspects are believed to have fired about 76 rifle rounds aton of the pursuit. 76 is our number we have right now, however on them on their person and in vehicle they had over 1,400 .223 caliber rounds that were available to them and had over 200 .9 mm rounds on their persons as well. >> sreenivasan: in addition,ç investigators found three pipeç bombs at the social services complex, attached to a remote controlled car that malfunctioned. f.b.i. and police also searched a home in nearby redlands. what they found inside was another arsenal. the search that took place revealed that there were 12 pipe bombs in that house or in garage

to that house. there were also hundreds of tools, many of which could be used to construct i.e.d.'s or pipe bombs.çç in addition to that, they had other material to produce additional bombs as well. >> sreenivasan: as the search proceeded, authorities began to piece together more on the shooters. sayed farook was 28 years old, born in the u.s. and worked as a county restaurant inspector. his wife, tashmeen malik, was in the country on a visa and had a pakistani passport. the couple also had a six-month old child. last night, farook's brother-inç law said he couldn't fathom whyç they did this. >> i have no idea, i have no idea why he would do that, why would he do something like this. i have absolutely no idea. i am in shock myself. >> sreenivasan: lori noble lives nearby and was buying a christmas tree today. for her, the attack was personal. >> i have a disabled daughter

and she gets services from there, and know quite a few tough. you don't expect it to happen here and it just did. >> sreenivasan: nearby at the original mommy helms bakery, they were on lockdown yesterday. does it make you feel less safe? >> yes, it does. because it is so close to home. it does make me feel unsafe. you have to have your guard up at all times, you just never know.çç >> sreenivasan: meanwhile, president obama appealed again, from the oval office, for the country to find a way to curb gun violence. >> so many americans sometimes feel as if there's nothing we can do about it. we're going to have to search ourselves as a society to make sure we can take basic steps that would make it harder not impossible but harder for individuals to get access to weapons.çç

>> sreenivasan: this is still a community in its early stages of grieving. just today, the coroner's office started making public the names of the 14 people murdered yesterday. that means this town will feel the ripple effects of their loss that much more acutely. there are vigils planned tonight to try to remember those affected by this, including one at the san bernadino mosque, the largest one here. gwen. >> ifill: thanks, hari.çç >> ifill: the san bernardino shootings prompted new debate in congress today on how to stop gun violence. senate democrats offered proposals to expand background checks and make it harder for people on terror watch lists to buy weapons. republicans opposed those amendments, and called instead, for overhauling the country's mental health system. >> woodruff: the u.s. military will open all of its front-line combat jobs to women, without exception. defense secretary ash carter announced the change today, rejecting the marine corps' request for exemptions.çç at a pentagon briefing, carter

said the military needs the broadest pool of talent for the toughest assignments. >> our force of the future must continue to benefit from the best people america has to offer. to succeed in our mission of national defense we cannot afford to cut ourselfs off from half the contry's talents and skills. we have to take full advantage of every individual who can meet our standards.çç >> woodruff: we'll hear gwen's interview with secretary carter a little later in the program. >> ifill: secretary of state john kerry says the islamic state group can be defeated within months, if there's a cease-fire in the syrian civil war. kerry made the prediction at a european security conference today. meanwhile, britain launched its first air-strikes overnight, against isis targets in syria, shortly after parliament approved the move. the british are using cyprus asç a base.ç >> woodruff: russian and turkish officials held their first high- level meeting today since turkey shot down a russian military jet, nine days ago.

afterward, russia's foreign minister said, "we heard nothing new." at the same time, president vladimir putin again accused turkey of buying oil from islamic state forces in syria. the turks called that claim "soviet-style propaganda". >> ifill: the corruption crisis engulfing international soccer has widened again in the(u/s. and europe.ç swiss authorities arrested two vice presidents from soccer's governing body fifa in pre-dawn raids today at a luxury hotel in zurich. and in washington, u.s. attorney general loretta lynch announced charges against 16 more officials of fifa's executive committee. >> the betrayal of trust that is set forth here is truly outrageous. and the scale of corruption alleged herein is unconscionable.çç and the message from this announcement should be clear: to every culpable individual who remains in the shadows, hoping to evade this ongoing investigation, you will not wait

us out, and you will not escape our focus. >> ifill: investigators allege that fifa leaders have accepted millions of dollars in bribes to influence the selection of sites for world cup matches. >> woodruff: the double-amputee olympic runner oscar pistorius is likely headed back to prison in south africa.çç an appeals court convicted him today of murdering his girlfriend in 2013. a lower court ruled it was manslaughter-- a lesser charge-- but prosecutors appealed. >> ifill: another verdict back in this country. a federal jury in west virginia has convicted a former coal executive of a single misdemeanor, in a 2010 mine explosion that killed 29 men. at the time, don blankenship ran massey energy, the mine's owner. he was found guilty today of conspiring to violate safetyç standards, but acquitted of morç serious charges. he plans to appeal. congress took action today on highways and health care. the house approved a five-year

bill funding highways and mass transit, to the tune of $305 billion. it also includes a separate provision to revive the u.s. export-import bank. in the senate, republicans moved a bill to repeal president obama's affordable care act.çç he's promised a veto. newly elected house speaker paul ryan served notice today that republicans will offer what he calls "a complete alternative to the left's agenda". ryan spoke today at the library of congress, and called for simplifying the tax code and rolling back obamacare, among other things. >> we want all americans when they look at washington to see spending going down, taxes going down, debt going down.ç we want to see progress and weç want to have pride. we want people to believe in our future again. we want a country where no one is stuck, where no one settles, where everyone can rise. >> ifill: ryan also said it's

time for major revisions in major social programs-- akin to welfare reform in the 1990's. >> woodruff: the secret service is in the spotlight again. a house oversight committee report today calls it an "agencç in crisis." the year-long investigation found: 143 security breaches, or attempted breaches at facilities guarded by the secret service in the last decade. it also said the secret service is understaffed and poorly led, and agents and officers are overworked. democrats on the committee said deep budget cuts are partly to blame. >> ifill: in economic news, the federal reserve is on track forç its first interest rate hike in nearly a decade later this month. that word today from fed chair janet yellen. she told congress that economic conditions seem right for a hike, and the fed's open market committee must act accordingly. >> were the fomc to delay the start of policy normalization

for too long, we would likely end up having to tighten policy relatively abruptly. such an abrupt tightening would risk disrupting financial markets, and perhaps eveeç inadvertently push the economy into a recession. >> ifill: meanwhile, the european central bank today cut a key interest rate and extended its stimulus program. >> woodruff: that disappointment with europe's rate cut sent wall street into a sell-off. the dow jones industrial average lost more than 250 points to close below 17,480.çç the nasdaq fell 85 points, and the s&p 500 dropped nearly 30. >> ifill: still to come on the newshour: when radicalization flies below the radar. the secretary of defense on today's historic announcement to dramatically expand the number of women in combat. the abuse of gays in nigeria, and much more.

>> woodruff: now, let's return to some of the questions out there about the murders in san bernardino. several news reports suggested the fbi is treating the shooting as a terrorist case. there's also been speculation as to whether the suspects could have been radicalized. again, there are many details still unclear, including motive. but let's discuss what we know with two who are familiar withç these issues.ç michael leiter is the former director of the national counterterrorism center. and, seamus hughes, deputy director of the program on extremism at george washington university. michael leiter, seamus hughes, welcome. michael, let me start with you. as we said we don't know the motive. we don't know if there was someç

workplace friction involved inç this. but we do know they had a lot of ammunition in their home, in the vehicle. we know they had traveled overseas, but they were not on any watch list. why not? what would have put them on a watch list? >> usually to be on a watch list there has to be reasonable suspicion of people being involved in terrorist activity. in this case you have individualindividuals who were - that is obviously not enough. you had people who travel to the middle east, pakistan and saudi arabia-- that is not enough. andçif you have details aboutt and it's particularly probative, that could get someone on a watch list, but i don't think we yet have enough information ton whether or not they were inappropriately or appropriately not on watch lists. >> woodruff: seamus hughes, you study people who are-- i guess the classification is extremists, people who are radicalized. what happens in that classification? what-- it changes someone from

being not radicalized to being radicalized? >> it's a very highly individualized process and each äplrson is different. and itç can range from a few weeks to a few months. and we've seen in each one of the cases that family members see something concerning every time. they see a train wreck happening in slow motion but they don't know what they're seeing. they don't know who to talk to in these situations. >> woodruff: we heard, i think it was the brother-in-law, of the man, the suspect here, saying the family in essence was shocked. he had no idea this was going on. >> and that's usually a general reaction. i would beç surprise surprisedr friends and family didn't see something, also, though. i would think someone saw something at some point and said, this, seems a little bit off," and just didn't know what to do after that. >> woodruff: michael leiter, how do authorities go about piecing information together? if he-- they were in touch with people who were being watched fthey were buying weapons, you know, when does that become critical mass? >> well a lot of?xáhat

information authorities mcy not actually know at the time. they may see calls going from someone who is on a watch list to someone else. they really don't have any indication at that point to look at these two individuals. what they'll do now, of course, is that forensic analysis. and what is so hard for authorities is after the fact, the monday morning quarterbacking, you can look at all those dots of information and say, "ah, of course. this is what happened." but before this is disparate pieces of information. the fact that someone goesç anç buys a weapon in the united states, there's nothing illegal. but it will now be, i think, the exploitation of the electronic media, their footprints online, their phone conversations-- all of those pieces will give authorities the best indication of whether or not there was an element of radicalization going on here. >> woodruff: seamus hughes, as you have looked at this population, i mean, how many people are-- are you studying out there who may have theç characteri:gr(:hjt someone who

would be prepared to pull off something like this? >> it's an ongoing investigation. we're still figuring out the exact moat and i have it may be a mix between workplace violence and terrorism, but in terms of isis recruits we lookedt cases of people in the legal system and the average age was 26, one-third were 21. the vast majority were male but we saw a number of females in the study. we see the demographic changes. >> woodruff: that's what i aç couple. we understand they were married. they had a young baby. they had been married just recently. they're both in their mid-20s. my question is does this fit the profile? >> i mean, that's the exact question. there's not a typical profile when we look at these cases. we've seen old and young, rich and poor, you could be a-- 40% of them are converts but the general population is 23. it runs the gamut on these type of things.ç in terms of the roleç of womenn these type of activities, it's not necessarily novel thing.

we've seen women play a prominent role as propagandists and recruiters. what is novel in this is the fact that she was a mass shooter and that's unlikely. >> woodruff: michael leiter, that makes the work of the authorities a lot harder, doesn't it? >> this is very, very hard. this is the counterterrorism and law enforcement official's worst nightmare. one or two individual with weapons who areç eitherç radicalized or motivated by anything, it's very hard to detect. we have some advantages over our european counterparts and some disadvantages. what we saw in paris is open borders making it very hard for europeans. the isolated muslim communities, makes it very hard for europeans. but here in the united states, the terrorists have a real advantage and that is easy access to weapons. it makes actually going to that step of violence thatç much eay harder for counterterrorism officials to ultimately stop. >> woodruff: you're saying

that's a contrast with europe. it's harder there to get the weapons than it is here? >> it absolutely is. in most european countries, the u.k., and france, issues of radicalization are more problematic. they are more isolated and again the open borders of europe make it harder to detect. we have some advantages there but theçdiéç access to weapons makes it harder to officials here. >> woodruff: again we want to stress we don't have all the information. in fact we really just have bits and pieces at this point, but seamus hughes, when you're looking at these individuals, is this something that happens gradually over a period of time? or does-- is there one incident that tend to make them snap and decide, "i'm going to go in that direction?" >> again, it's a highly individualized process. we've seen months. but withç theç advent of socil media the process has shrunk considerably and usually there is some sort of trigger event, something that pushes someone over the edge. they already have this world view and one more thing triggers them to action.

>> woodruff: michael leiter, i think the question on a lot of people's minds tonight is what more can be done to identify individuals who may be at risk of doing something like this? >> well, i don't want to say it's impossible to stop these, but it's very, very difficult. i do thinkç that makingç sure t individuals who are on the watch list-- not this case-- are checked when they buy weapons. i think that's a critical step. we then have to have really deep engagement with muslim communities in the united states so those communities feel they are a partner. it is not adversarial between law enforcement and them. and they will identify these individuals, they will report them. we're not always going to have indicators, so what intelligence can do is find those place where's we have indicators, whether it's travel or online activity, andç then relyç on e communities to partner with government officials and make clear that this is not a war of the u.s. versus islam but in fact it is a partnership against people who are pursuing violence for any number of reasons. >> woodruff: michael leiter, seamus hughes, we thank you

both. >> thank you. >> woodruff: and for any updates, we will continue our coverage of the story throughout the online at pbs.org/newshour.ç >> ifill: in announcing his decision to fully open the ranks of the combat military to women, defense secretary ash carter said the u.s. cannot afford to ignore half its population, especially at a time when new challenges await. i sat down with the military's top civilian today at the pentagon to talk about thatç historic change, and aboutç taking the fight to isis, at home and abroad. mr. secretary, thank you so much for joining us. today, you announced that you're going to open many combat roles in the military to women. there had been the countless reports about the pros and cons

of this. how did you finally reach your decision? >> well, we had done, over a period of several years, a number of studies. we'd surveyed the force, done experiments, and then iç receiç recommendations from the subject of the army, the secretary of the navy, the secretary of the air force, the head of our special operations command about women in special operations, and all of our joint chiefs of staff. and i took all that data and all their suggestions and recommendations into account, and came to the decision to open up all remaining military specialties to females. and the reason for that is simplyçç this-- we have an all-volunteer military. and in order to have, as we have in the future what we have today-- which is the finest fighting force the world has ever known-- i need to be able to reach into the entirety of the american population. remember, an all-volunteer force. so i want to recruit from all

pools. >> ifill: you said today equality of opportunity did not guarantee equality of participation. >> no. >> ifill: explain what you mean beç that. >>fere are some areas, for example, some of the specialties being opened up today, where physical endurance and raw physical ability is an important part of, for example, loading an artillery piece. now, there are women who can do that and there are women who can do it better than some men. but you can't-- the data shows very clearly that on average, women in that age cohort don't have those physical abilitiesçç as great a proportion as men do. so you can expect specialties like that will not have as many men in them-- sorry, women in them as men. and we need to-- remember, we need-- what we're focused here on is mission effectiveness, protecting our country and protecting our people. that's the principal reason to

do this. and so, we're going to need to do it according to standards. >> ifill: it has been-- >> no quotas. >> ifill: no quotas.ç it has been widelyç reported, however, about the disagreement among some ranches of the military about this, including, among them, the marines. how did you cope with those objections that this would be a threat to union cohesion, that this would be a social experiment gone wrong? >> well, all of the service secretaries and the head of special operations command and all of the joint chiefs of staff, except one, recommended that we open up all of the specialtiesç forç which they e responsible. the commandant of the marine corps recommended that we open up most marine corps specialties, but not a few. i listened very carefully to what he said, particularly since he's the same person-- this is general joe dunford-- they recommended to the president be the chairman of the joint chiefs of staff. and, therefore, my and the

president's senior military adviser. so he's a man of great experience and wisdom. i listen toçç him in everythi. i listened to him in this regard as well-- >> ifill: and yet you overruled him in the end. >> in this regard i came to a different conclusion. i agreed with much of what he said, but not that particular matter. >> ifill: if you compare this to other turning points in the military, the intexwraigz of the force, don't ask-don't tell, the adjustment to cyber warfare, how does this rank in terms of the potential change this will bring to the nation'sju8áv >> well, i'mç incredibly proudf this place because when they take something on, they do it well. when they took on new technology-- you mention cyber-- they take it on well. when we took on don't ask-don't tell-- we did it in a you quality, thoughtful way that made it a success, as don't ask-don't tell has been-- we'll make a success of this as well. >> ifill: i want to change the topic for a moment, talk to you a little bit about smugç testified to congressç about

earlier this week which is our escalation of american-- for lack of a better phrase-- boots on the ground in iraq and syria. you said we are at war. could you better define for me what that means. >> well, i was using it in a very commonsense way, not in a legalistic way. this is an enemy that must be defeated, that will be defeated. it requires a level of commitment andç dedication and peffort on our part that deservs that word. >> ifill: how effective can you be when prime minister abadi, and many-- everyday iraqiss look at the idea of an increased u.s. presence as a threat? >> prime minister abadi welcomed the u.s. presence, and he has-- >> ifill: he sent kind of a mixed message on that. >> well, i think what prime minister abadiç wants and receive is that is he is consulted, and we have his consent every time we operate in

his country. now, it's true that prime minister abadi, even though i believe-- i've talked to him many times-- has the right ideas for the future of iraq, baghdad's a complicated case, and he doesn't always get his way. that we watch very carefully. >> ifill: so there's a little internal politics going on?ç >>ç enormous internal politics there. and some of that's okay. abadi's strategy towards governing iraq makes sense, what he calls decentralization, so sunnis, kurds, and shia all live together in one country. they're not at each other all the time but they have enough localized rule that they're not under each other's thumb. that's as good as it gets in iraq. >> ifill: i know you are aware of the criticisms that come from capitol hill because you wereç there, and theç committee chairman mac thorn berry told us the night you testified on the newshour that your approach is too gradual, we're being

responsive rather than acting, and that the white house is essentially micromanaging our military action from, as he put it, the basement of the white house. >> not true. we are looking-- we're not reacting. we're actually on the initiative. we're looking for every way we can to attack and destroy isil. the strategy, theç fundamentals ofç our strategy in iraq and syria is that not only to defeat isil, but to inflict a lasting defeat. as far as the white house is concerned, the president taeld me the same thing i tell our military commanders, which is when you have another way of going at this, we're going to do it. now, we just-- what i was describing up on capitol hill earlier is several different ways that we've improved our campaign just in the last fewçç weeks. the expeditionary targeting force, which will be a force that will come in at night and capture people, kill leaders,

destroy, seize, get hostages, free hostages-- as we did a few weeks ago-- and cause every isil leader throughout syria and iraq to wonder whether the americans are going to come tonight. >> ifill: you are describing warfare that(wd are familiarç with, but isil, as far as we can tell, given what happened in paris and what may be happening here within our own borders, is far more all over the place than that. how do we deal with the idea that isil is radicalizing enemies around the world, that boots on the ground can't approach? >> well, exactly right. and that's why its boots are important in iraq and syria-- by the way, i just remind you that we have 35 hundred boots on the ground in iraq. people talkç about boots on thç ground. there are boots on the ground, and they're doing an excellent job. >> ifill: not enough, by the way, is what mac thornberry says. >> that's what i said as well. we're looking for opportunities to put more on. but to get to your other point,

yes, the fight changes around the world, changes from a place like libya or afghanistan where some mostly former taliban members have taken the isil flag up. and those need to be dealt with here to the united states, where we've had people, some of them just loser-- losers with a keyboard, who get exciteed by isil propaganda and decide to take off against our fellow citizens. so this is the first-ever social media enemy. and so it's a-- it's new. now, it's something we can defeat, but we have to beç ingenious, and t@a( committed to thinking and working and adapting so that we change our techniques and our avenues of attacks so they don't know we're taking them by surprise, and we're doing new things to defeat them. that's why i say it's a dynamic

campaign. what i was saying on capitol hill earlier this week is here are the new things we've done just in the last two or three weeks. we're going to keep doing that until they're defeated, which they willç be. >> ifill: secretary of defenseç ash carter, thank you very much. >> thanks for having me. >> woodruff: we now turn to our series "nigeria: pain and promise." tonight, special correspondent nick schifrin details the abuse and mistreatment of gays in the country-- by law enforcement, and by muslim and christian groups.ç a warning: it contahís some disturbing images. >> reporter: in nigeria this house of god has become eye home for hate. do you believe that gay men deserve the same rights as everyone else?

>> the gay man knows that because of his practices, he has no right equal to another person. >> reporter:ç reverendç joshua maynard leads the state's 50,000 christians. as the service begins, the band starts a hymn about christ's sacrifice. and then it delivers a warning. "end times are here." reverend maynard says they're here because of one thing. >>ç homosexuality.ç sodomy. it is evil to this country. it is evil to our culture. it is evil to what believe and that is christianity. it is evil to what we inherited from our fathers. it is evil against anything that we hold so dear. preach against them. stand against them. if you want to go by them, the wrath of god will fall upon you.

>> reporter: in the west, his sermon has become the outlier. in nigeria, it's redç meat. >> and i think that is one of the reasons why soadom and gomorrah, had to be wiped out because of homosexualism. >> pope francis said, "who am i to judge a gay man?" why do you think you should judge? >> reporter: the problem is a!at's exactly what'sç happene. last january, nigeria made same-sex marriage and advocating for gay rights crimes. since then, nobody's been sentenced, but police, state-sponsored vigilantes, even public mobs are accused of exploiting the law to abuse and export.

in another video, a mob accuses a man of beingç gay.ç and then the accusers take off their belts. gay nijeernz say since the law was passed, had kind of abuse has become common, and not just by vigilantes. çç >> reporter: brian says police officers picked him off the street and beat him inside this police station. >> reporter: in legos, brian and a group of gay men agreed to meet and openly discuss their

homosexuality.çç >> reporter: simmion is gay and h.i.v. positive. >> reporter: you considered committing suicide? çç >> why do you think this law is actually passed? >> reporter: the law doesn't only punish same-sex marriage. by advocating for gay rights, these men could be sentenced to 10 years. by talking to them, i also could be sentenced to 10 years. >> we're responsible for ourselves. >> yes. >> okay. we cannot have heterosexuals come and be responsible for you. >> 27-year-old peter cass is the group's organizer.

here has been aç gaeç rights activist since before the law, ever since one day in church his pastor told him. >> you're gay, you're perverted, you're possessed, all slandering words and they needed deliverance and i was trying to bring sodomy and gomorrah, into the church. >> reporter: can you show me your house? >> okay. >> reporter: down the street, cass shows me the safe house he runs for gay men and women.ç it's often o]erwhelmed. and you have to share this space with how many people? >> seven people, sometimes. >> reporter: you said yourself this is relatively basic. do you wish you could offer more? >> yeah, i wish i could offer more seriously because we have too many issues of the l.g.b.t. being kicked out of their homes because they are gay. >> reporter: when brian told his family he was gay, he was disowned.çç

>> reporter: as difficult as life is for gay christians in nigeria, it's worse for muslims. in northern nigeria, the bouche security committeeç enforces tç state's islamic law. every night they walk through alleys and markets, hoping to punish what they consider vice. for them, the criminals include gay men. their leader believes homosexuality is the same as pedophilia. why do you equate gay activity with pedophilia, with children? ç >> reporter: after they patrol, they're calm.

in this community, they're the hunters. their prey are terrified. çç >> reporter: can you tell me what the vigilantes did to you? >> reporter: these three men are gay and muslim and live in northern nigeria under islamic law. it's too risky to show their faces.çç >> reporter: because what would happen if you displayed your swullity? what happened when your family

found out you were gay? >> reporter: quit being gay? ak >> reporter: you were forced to get married. what's that like? >> reporter: newly elected nigerian president has promised change, but so far, that doesn't extend to gay men. on twitter,ç a spokesman said ç a meeting in washington he was point blank. sodomy is against the law in nigeria and abhorrent to our culture. in a second tweet the spokesman added, ," the issue was not

pushed." u.s. officials tell pbs newshour they don't push the issue because they fear public criticism would backfire. but gay nigerians say that policy helps increase public hate and private pain. >> when somebody tells you, you cannot amount to anything becauseç of yourç sexuality. when a passer tells you you're going to go to hellfire because you're homosexual, a lot of people's spirits get broken. sometimes i get calls, i get text messages, i get e-mails threatening my life. that's-- if you don't stop what you're doing as an activist, as a gay activist, then, we'll kill you. sometimes i get scared but i tell myself, no. if i don't fight, who will? >> reporter: that courage comes from the brotherhood that their religions and their stateç try toç deny them. >> on a day like today, when you're with this group, how do you feel? >> reporter: where do you get

your courage from? çç >> reporter: nick shifrin, pbs newshour, in northern nigeria. >> woodruff: tomorrow night, nick schifrin will be here in studio to wrap up his nigeria reporting, and he will be joined by the nigerian writer chimamanda ngozi adichie. >> ifill: we'll be back with a look at the economics of climate change. but first, take this moment to hear from your local pbs station. it's a chance to offer your

support, which helps keep programs like ours on the air. >> ifill: for those stations still with us, we take a look at neuroscience and its influence on education. thousands of teachers around the country are learning about an alternative teaching approach, using scientific discoveries about the brain to improve the way children learn in the classroom. special correspondent john tulenko of learning matters reports from philadelphia. >> when i say class, you... >> you stop what you're doing. look at the teacher. >> reporter: today is wacky wednesday in jasselle cirino's third grade classroom, which explains the blue wig.

>> so i want you to teach your neighbor. >> reporter: the rest of what you're about to see is what her classroom looks like every day. >> i want giant gestures. >> reporter: she uses a set of techniques some call whole brain teaching. >> a lot of times in traditional teaching, you're just lecturing, and you're talking and talking. and what we like to say, whole brainers, we like to say that the more you talk, the more students you lose. and so we use different methods to engage multiple parts of the brain. and that way, you get 100% engagement. >> reporter: these days, scientists can look further into the brain than ever, pinpointing the neurons and circuits that control how we think and act. all that's sparking a movement that's changing the way some teachers teach. are there parts of the brain that you're aiming at? >> yes, the hippocampus, the motor cortex, the prefrontal cortex, which is the brain's boss, so something like class,

it turns on the prefrontal cortex, which makes the brain's decisions. so it says, "hey, pay attention. i'm about to tell you something." so, once i have their attention, i teach the material usually through mirrors. this deals with the mirror neurons in your brain. and so what i say, they repeat. to learn anything, you have to repeat something. you have to repeat something that's modeled to you. that's where it starts. >> reporter: a lot of times in your class, i saw you gesture, and then you asked your students to gesture. >> right. that's for engaging their motor cortex. when you act things out while you're reading, you comprehend more. and we use brainees. these are gestures that are tied to writing skills. >> reporter: can you give me some examples? >> sure. for example is an example. but

or however. if, then, so more of like a cause and effect. adjective. a noun is a person, place or thing, compare, contrast, simile, metaphor, i mean, the list goes on and on. >> reporter: i saw you a bunch of times where you would stop, and then you would say to the group, teach. >> teach. >> reporter: what's going on there? >> so i have taught them the lesson, but now they need to teach that main point to each other. they're getting another repetition of the material, but, this time, a lot of times it's in their own words. and they're learning how to put things in their own words. you're writing while you're doing it. you're gesturing, so you're remembering it in different parts of the brain. you're not just listening. you're also speaking. you need to be doing all of these things at once in order to engage the whole brain. >> reporter: we wanted to know if science actually backed up any of this.

so we brought a video of jasselle's class to daphna shohamy, a neuroscientist at columbia university. >> i buy it. it makes great sense to me. i mean, the brain is really in many ways wired for actions, right? it's - it's really not wired to sit passively and absorb any information. but i think where - you know, where i wouldn't fully agree is the idea that more activity is always good. more brain activity in more places doesn't equal more learning or a better memory. >> reporter: ok, how can children learn better? >> right, right. yes, it's the million-dollar question. i think we have some answers. the brain learns when things are surprising and interesting. >> what is going on here? >> so if i give you a $20 bill, now, all of a sudden, you will sort of have a burst of activity in your dopamine neurons. they fire. but if i do that regularly, like every five minutes, i give you $20, your dopamine neurons will stop firing.

so what these neurons are doing is they're signaling how unexpected an event was in the world. they're not signaling how good or bad it was. they're signaling how unexpectedly good or unexpectedly bad it was. so keeping things a little bit noisy and a little bit different is actually really beneficial for learning in many different ways. >> hold your horses. >> reporter: neuroscience says there's something else important going on here. >> when you're learning things, just even in life, you connect it with a type of feeling. and so the main emotion we want you to feel in a whole brain classroom is fun. >> seriously? >> our brain was evolved to survive. we need to remember things that were of emotional and social significance. that's probably much more important than remembering any bit of information that was communicated to us within a lecture. >> we're done being blah. it's time to get fuzzy. >> fuzzy!

>> reporter: here are a few other things neuroscientists think the rest of us ought to know about the brain, that stress damages neurons and impairs learning. brain training games claim to be effective, but, in fact, the jury's still out. what does help is regular physical exercise. staying active keeps the brain developing and delays cognitive decline as we get older. in philadelphia, pennsylvania, i'm john tulenko reporting for the newshour. >> ifill: i'm thinking about a blue wig. found >> ifill: a study of one california elementary school that used so-called "whole brain" teaching, found math and language art test scores at the school rose by 11%.

>> woodruff: diplomats in paris have spent much of this week trying to work on a new accord on climate change and emissions cuts. much of it is aimed at holding the rise in global temperatures to about two degrees celsius. last night, william brangham explained why that threshold is so important. tonight, economics correspondent paul solman reprises his look at an even more dire scenario. it's part of our weekly segment "making sense", which airs every thursday on the newshour. >> look, you can start to see erosion along here. >> reporter: economist marty weitzman thinks his property on a marsh in gloucester, massachusetts, is washing away due to climate change. >> the water has risen a couple of inches at least in the time, in the 40 years i have been living here. >> reporter: right. >> and what's happened is that it's caused erosion at the edge of the lawn.

>> reporter: well, but a couple of inches doesn't seem like much. >> maybe that wouldn't be, but it's really a couple of feet that we're headed for. >> reporter: a couple of feet, or conceivably, several dozen, says gernot wagner, a former student of weitzman's who's now at the environmental defense fund. last time concentrations of co2 were as high as they are today, we did in fact have sea levels up to 66 feet higher than today. well, 66 feet and this house is gone. >> reporter: now, weitzman and wagner can't know for sure, of course, that manmade higher temperatures are rising the tides here or anywhere else. but a plausible probability of true catastrophe was enough to prompt "climate shock," about the dangers that lurk, dangers weitzman wasn't worried about when he first went into environmental economics years ago. >> i was wondering, how could it be possible that mere human beings could change the climate in a serious way? >> reporter: but geologic

samples of carbon dioxide going back millennia changed his mind. >> we were way outside the historical range for at least 800,000 years, and we're climbing very strongly. >> reporter: today's higher concentrations of atmospheric carbon dioxide are shown here in red. and the historic correlation with high temperature implies, says weitzman. >> there's about almost a 10% chance of an increase of 4.5 degrees centigrade. >> reporter: and that's nine degrees fahrenheit, roughly speaking? >> yes, something like that, and that would make outdoor living in many parts of the world impossible. >> it doesn't sound like a lot, but think of the human body, right? if you have a fever of 4.5 degrees centigrade, nine degrees fahrenheit, you are dead. >> reporter: but 10%, i mean, that is just one chance in 10. i have been at the racetrack long enough to know how rarely a 10-1 shot comes in. >> yes, but we...it's not that rare. you buy fire insurance for

probabilities that are much lower than 10%. you buy car insurance for probabilities that are much lower than one in 10 over a lifetime. so, this is well within the range of things that we like to insure against. >> reporter: ok, buy insurance against catastrophe. but how? one set of solutions are technical, like solar radiation management, shooting particles into the sky to reflect sunlight back into space. harvard environmental scientist david keith. >> the central idea is to make the planet a little bit more reflective, which tends to cool it down, because it will absorb less sunlight. and that will partially and imperfectly compensate for the buildup of greenhouse gases like carbon dioxide, which are tending to trap heat and make the earth warmer. the technique is cheap, feasible. but like any new technology, it carries risks of its own, like overcooling the planet. gernot wagner prefers the economic solution. >> you price co2. you price carbon dioxide.

>> reporter: you put a price on it? >> that's the insurance premium, right? for every ton of co2 we are emitting today, we cause at least about $40 worth of damages. when i board a cross-country flight to san francisco and back, i emit about one ton of co2, i personally, not the plane, just me personally. meanwhile, i don't pay for that. >> reporter: so you want the airline to charge an extra $40 on your ticket? >> i want the government to put a price on co2 that everybody pays, in order to set the right incentives. >> reporter: it's a market-based solution that appeals to economists left and right, but remains politically unpopular. >> this was once a red cedar. >> reporter: ultimately, economists believe in weighing costs against benefits and to marty weitzman, the benefit of preventing true disaster, even if it's only a 10-1 shot, far outweighs almost any short-term costs. meanwhile, the costs of inaction seem to be inching ever closer to home.

>> so here is a wooden walkway that has been lifted up by high tides that will come over it. >> reporter: so you mean this was flat before? >> yes. when it was constructed, it was flat. careful. >> reporter: it isn't anymore. this is economics correspondent paul solman, reporting for the pbs newshour, from gloucester, massachusetts. >> woodruff: on the newshour online, meet a young millionaire who's made it his mission to rescue migrants on the open sea. now he cruises the mediterranean in his own ship, to look for migrant boats in peril. p.j. tobia talked to the founder of migrant offshore aid station, on the podcast shortwave. find out how to listen, on our home page. all that and more is on our web site, pbs.org/newshour.

>> ifill: tune in later tonigt, on charlie rose: the latest on the san bernardino shootings, and the former acting director of the cia michael morrell. and that's the newshour for tonight. on friday, jeffrey brown sits down with famed director spike lee to discuss his new film chi- raq. i'm gwen ifill. >> woodruff: and i'm judy woodruff. join us online, and again here tomorrow evening. for all of us at the pbs newshour, thank you and good night. >> major funding for the pbs newshour has been provided by: ♪ ♪ moving our economy for 160 years. bnsf, the engine that connects us.

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>> this is "bbc world news." >> funding of this presentation is made possible by the freeman foundation. newman's own foundation, giving all profits from newman's own to charity and pursuing the common good. kovler foundation, pursuing solutions for america's neglected needs. and hong kong tourism board. >> want to know hong kong's most romantic spots? i will show you. i love heading to repulse bay for an evening stroll. it's a perfect, stunning backdrop for making romantic