♪ brent: this is "dw news," live from berlin. tonight, the trump tweet threat. the u.s. president fires off a warning to russia over syria. in a tweet, he wrote, get ready russia, missiles will be coming. an alleged poison gas attack last weekend brought the trumpet to value strike military targets. and the death toll climbs to 257 in a military plane crash in nigeria, one of the deadliest disasters in aviation history. they have begun three days of mourning.

and facebook's boss faces day two of questions in congress. mark zuckerberg's tells lawmakers he thinks it is inevitable that social media will be regulated in the united states. ♪ brent: i'm brent goff. it's good to have you with us. u.s. president donald trump has blasted off a warning to russia over syria. and he has done it via twitter. the u.s. president threatened military action in retaliation for an alleged poison gas attack last weekend. syria's army has saught to hide its military aircraft because of fears they might be targeted. several western nations believe the poison gas attack was carried out by syrian government forces using bombs that were filled with toxic chemicals. reporter: these images shocked the world.

survivors of an alledged chemical weapons attack in duma last saturday. this has sent tensions between russia and the west to new heights. president trump took to twitter to warn syria's main backer. get ready, russia. you should not be partners with a gas killing animal who kills his people and enjoys it. u.s. secretary of defense james mattis said the u.s. military was still assessing the situation, but did not rule out a strike. >> we stand ready to provide military options if they are appropriate. reporter: u.s. warships left port on wednesday en route to the middle east. they are not due to arrive for weeks, indicating washington means to keep up the pressure. meanwhile, russia has moved fast to establish itself in duma.

this video reportedly shows russian police investigating new the site of the attack. moscow says it and the regime are ready to allow a probe, which should not give blame, and the kremlin offer caution. >> we support a serious approach. we still believe that it is important not to take any steps that may harm the already fragile situation in syria. we are also still convinced that the excuse regarding the use of chemical weapons in duma is made up and cannot be used as an argument for military action. reporter: the alleged attack has already shifted serious battlelines. here, displaced people from duma arrive in serious rebel held north. the refugees are a reminder of the brutal intensity of this war, which the international community has so far remained powerless to stop. brent: we want to take the story

now to the u.s. and the russia. our correspondent claire richardson is standing by in washington and our chief is standing by in the russian capital. i have a question for both of you. a u.s. strike against russian sources in syria, how credible is this threat by u.s. president trump? clare, i will start with you. clare: at this point, a military strike certainly seems that a real possibility. if trump decides to go this route it will not be the first time his administration has carried out strikes on syria. it was just about a year ago this time of year that the united states took its first military action against syria, striking an air base in an effort to punish the assad regime. so the question becomes if this ad hoc attack we saw last year was ineffective as a deterrent

to prevent assad from using chemical weapons against his own people, then what would it be about a strike again, a single shot that could potentially change his calculation this time? it is also unclear what trump's long-term plan on syria really is. it was just earlier this month he was saying he wanted to pull all u.s. troops out of syria. that was against the advice of his military advisers, who said they wanted to stick around and make they had the so-called islamic state in check. now we're seeing him openly calling military strikes in looking very well escalate the situation. brent: is moscow taking trump and his tweet seriously? yuri: well, moscow has to take it seriously. that is why moscow at least publicly is taking to strong warnings. senior russian lawmakers said president trump's tweets

represents a dangerous approach to a critical situation. they also said it was really scary to think what kind of people control the largest military arsenal the planet has ever seen. a spokesperson for president vladimir putin said -- on the other hand, russians say very clearly they will not hesitate and would fight back if needed. brent: we are getting a report just coming across that u.s. president trump has said he holds syria and russia both responsible for a chemical weapons attack last weekend. that is just coming across on the wires. clare, let me pull you win. let's look at a -- pull you in. let's look at another tweet in which he said this.

our relationship with russia is worse now than it has ever been, and that includes the cold war. this is not the donald trump we have known the last two years. busy doubling down on russia to take some of the charge out of special counsel mueller's rush investigation? clare: the mueller investigation has definitely been dominating the headlines here in the u.s. however, the president is risking a direct confrontation with roscoe dash russia with this kind of rhetoric. -- confrontation with russia with this kind of rhetoric. an intervention in 2015 was widely seen as changing the course of the war in favor of bashar al-assad's government.

we're talking about humanity. -- we are talking about humanity or a crisis which has displaced millions. any action from the u.s. will require a serious long-term strategy and it is not apparent that trump has that. brent: pressure we know has already outlined how it would respond in the event of a u.s. strike. walk us through that. yuri: russia's ambassador to lebanon said in case of an attack, moscow will shoot down any u.s. missiles fired at syria. also, russia would obviously target launch sites of the missiles, which means u.s. military bases or aircraft carriers. a few weeks ago, i myself was embedded on the largest u.s. aircraft carrier in e world, in which missiles attack syria

and iraq. that worship was one of the largest warships in the world with more than 5000 marines and u.s. navy officers on board. if russians attacked -- brent: we know that vladimir putin has called on israel not to take any action that could further destabilize the situation in syria. asking tel aviv not to fire any shots. is the kremlin concerned that it could quickly lose its power and its influence in syria? juri: i don't excel. -- i don't think so. i think they are worried about a potential u.s. attack in syria. the kremlin wants to avoid direct confrontation with washington, i am sure.

i also think americans do not want a war with russia. so israel in this very complicated context seems to be just one more player in the region who also tries to achieve its own goals. russians obviously don't want any additional trouble, at least on this front. and they don't want israel to pour even more oil on the fire. brent: we are also getting a report that the white house is saying that all options remain on the table in dealing with this alleged chemical weapons attack in syria. so we don't have any clarity to report tonight. what about the american public? does trump have popular support for his offensive course in syria? clare: we don't have polling

numbers for this particular possibility of a strike, but we know that for his strike last year there was a majority of it will be remain to seeing if this will be equally as popular or whether people look at the past year and a president's pass comments and have a change of heart. brent: our correspondence at the white house and in moscow. both of you, thank you. the german chancellor angela merkel has also been commenting on the tensions over syria. she says she regrets the failure of the un security council to agree on how to investigate suspected poison gas attack. >> it would have been good to have an investigation on the ground, as the american resolution suggested. there are strong indications that point towards the syrian regime, and we will continue our assessments on that basis.

in any case, we utterly condemn the use of such weapons. brent: angela merkel speaking, earlier today. here are other stories making headlines around the world. yulia skripal, was poisoned along with her father last month, released a statement saying he will not accept an offer of help from the russian embassy. british authorities play moscow for poisoning her and her father with a nerve agent. her father remains critically ill in the hospital. saudi forces have intercepted several ballistic missiles filed i houthi rebels in yemen. witnesses reported hearing a number of blasts in the capital riyadh. they have been posting videos on social media showing smoke in the sky. there were no reports of casualties or damage. in the u.s., the republican house speaker paul ryan says he

will not run for reelection when his term expires in january. ryan's decision as seen as another blow to the republican party as it tries to maintain its majority in the house of representatives during elections later this year. the boss of facebook, mark zuckerberg, has answered more questions today from u.s. lawmakers about data privacy. zuckerberg testify following revelations that millions of people had their facebook data misused by the political consulting firm cambridge analytica. as he did yesterday, zuckerberg begin by apologizing to lawmakers over the scandal, which has so far affected 87 million users. during questioning, zuckerberg told a democratic lawmaker that he was among those whose data was improperly shared. take a listen. >> was your data included in the data sold to the malicious third parties? your personal data? >> yes.

>> it was. are you willing to change your business model in the interest of protecting individual privacy? >> congresswoman, we have made and are continuing to make changes -- >> no, are you willing to change our business model in the interest of protecting individual privacy? >> congresswoman, i am not sure what that means. brent: with me here at the big table is our social media editor . what was different today or what did zuckerberg say today that was different? carl: day tow in the books, a marathon -- day two in the books. i think this house committee had the better questions than yesterday. i think mark zuckerberg dig very -- did very well. if you would have to say one side had the upper hand it was definitely mark zuckerberg. that was definitely an intense

exchange there. he was also asked if he was going to minimize the amount of facebook data collects. he didn't have an answer for that question either. also interesting to see several lawmakers grilled him about illegal opel we would cellars or pharmacies -- illegal opioid sellers. he didn't have a good answer on how to prevent that. i was also interested to see what was not aed. he wasn't really asked if he should step down as the ceo of facebook. he is very powerful. he makes all the decisions. he wasn't asked if facebook should be broken up as a company. it wasn't really much on facebook's role on the racial or religious violence income -- countries like sri lanka. i want to see those asked. brent: a lot of good points. zuckerberg defended facebook's business model.

but he did make at least a couple concessions today. let's take a listen. >> i think it is inevitable that there will need to be some regulation. so my position is not that there should be no regulation, but i also think that you have to be careful about what regulation you put in place. a lot of times regulation by definition puts in place rules that a company that has resources like ours can easily comply with, but that might be more difficult for smaller startup. brent: i think it is interesting, i really don't understand why they would ask him if he wants regulation. what is he going to tell them? if he says yes, that will make him look like he doesn't know what he isalking abo. if he says no it is going to make him look like the bad guy. carl: mark zuckerberg is a smart guy. he knows regulation is on the horizon whether he likes it or not. he can't do much about that but what he can do is be on capitol hill and try to be what he wanted to be. there is -- what he wants it to

be. there is regulation in the eu coming into effect on may 25. today zuckerberg said clearly he likes those regulations and that he will implement them for all of the facebook users as much as possible. so there is regulation coming and it is not because of congress, not the house, not the senate. it is because of eu lawmakers. brent: whais ieresng or the past few days, we have seen him say time and time aga how he wants to focus on building community. he has talked about that more than privacy tools how to protect yourself. do you think he focused o community because he wts t die r atntion awayrom the problems carl it a b buzord r hi he loves that word, community. what he has done during these hearings is evade questions about what he is doing behind the scenes. how does he track users, that is a big focus that was not touched on much.

it tracks people who are not on facebook, it attracts people who did not even have a facebook attack. if you visit a page that has a facebook like button, facebook contract that person even if they don't have an account and use that activity for their own advantage. brent: and he hasn't said what is inside those algorithms. thank you very much. javier joins us now with business news and a look at the economic angle of this election. javier: needless to say there is a lot at stake for space -- at stake for facebook. mark zuckerberg his nose data is the -- mark zuckerberg knows data is the most important thing he has. it is clear he is not willing to give it away, no matter how much he says he respects our privacy. >> yes or no, will you change settings to minimize the

greatest extent possible the use of uses data? >> we try to collect and give people the ability -- >> yes or no. will you make the commitment to change all the user default settings to minimize to the greatest extent possible the collection and use of users data? i don't think that is hard for you to say yes to. >> congressman, this is a complex issue that i think deserves more than a one-word answer. >> that is disappointing to me because i think you should make that commitment. maybe what we could do is follow up with you on this. javier: we will leave that interpretation to you. meanwhile, tensions between russia and the u.s. are not only dragging down the markets, but also the russian currency. russia's ruble is falling fast. let's take a look. it has plunged to just over 15

u.s. cents, a value we have not seen for 18 months. since news of the sanctions last friday, rushers currency has dropped about 12%. reporter: the sanctions russia -- the sanctions announced against russia are already being felt on the streets of moscow. the ruble seems to be losing value by the hour. the u.s. says the sanctions are in response to charges of russian meddling in u.s. elections and other issues. but the russian prime minister continues to say they are really designed to give the u.s. and unfair advantage. -- an unfair advantage. >> it is an attempt to fight us through unfair competition, to limit our development, and to create tensions on the economy and the currency. reporter: for the time being, the plummeting euro is a more acute problem. that is because everyday russians know that a weak ruble

means trouble is just around the corner. >> the sanctions will have negative consequences, and a growing exchange rate of the dollar and the euro is a first indication that our economy with experience a drop. -- will experience a drop. reporter: and as the rhetoric heats up over the conflict in syria, the ruble continues to slide. javier: something on the latest rage among wealthy collectors. dinosaur bones. an auctionousen paris sold two fossilized skeletons for more than $1.4 million each. turns out dinos skeletons have become trendy. interior decorations for people who probably have to much money. the auction house is targeting private collectors does it typically pay more than museums. the specimens for sale are a-- f

you don't know what they are, just ask your kids. that is all for business. brent: they will know what they are. they know anything with an "asa urus." an investigation is underway tonight in nigeria after 257 people were killed in a military plane crash. the aircraft was packed with soldiers and their families when it crashed soon after takeoff in the capital algiers. the death toll makes it one of the deadliest plane crashes ever. three days of national mourning have begun in the country. reporter: rescuers pick through the rubble at the sight of algeria's worst-ever plane crash. hundreds of people were killed when a military aircraft came down in a field near algiers. on board, soldiers and their families. >> when my neighbor and i arrived, we found piles of bodies. it's a disaster, an absolute disaster.

reporter: this man escaped with his life. >> the plane fell just after taking off from the base. it fell first onto its wing and it caught fire after it hit the ground. i had just enough time to say a prayer. reporter: the body inescapable. the soviet made-model is used to transport soldiers to remote locations. the plane had just taken off from his home base. it was headed for morocco, but it never got there. an investigation has been launched, the cleanup has started, and algeria has begun three days of mourning for the hundreds of people who lost their lives. brent: the doping scandal that

rocked the 2014 winter olympics in sochi is spilling over from russia to austria and norway. the headquarters of the international biathlon union was rated tuesday evening by austrian police. a search warrant alleges a cover-up of doping cases during the sochi games by the sport's governing body. at the center of the investigation, the president of the federation since 1992. two football, and roma produced one of the greatest comebacks to knockout spanish giants barcelona. they were 4-1 down, but turned the match on its head with a 3-0 victory in rome. they got off to the perfect start in just six minutes. then a penalty doubled their lead, before they completed the

turnaround, sending the team through on away goals. as you can probably imagine, celebrations went on long into the room night, including for the -- plunging into the fountain. the last time roma made it to the semi final stage was in 1984. someone was wet, there. for most people, just one go at climbing mount everest is enough, and perhaps too much. but sherpas do it all the time. but even they have their limits. now one is attempting to make a record-breaking ascent. reporter: he is on firm footing as he prepares to climb the

mountie -- mighty mount everest. he stocks up on new gear, but h e's an old hand. at 48, he aims to be the first to reach the summit 22 times. >> i have already scaled everest 21 times. my last climb was last year. this year i am going to attempt to scale everest for the 22nd time to break a record. all my family and friends are very supportive and told me i should not stop climbing and should continue. reporter: the first conquered the world's highest mountain at 24 and has been back almost every year since. now he owns a comfortable living guiding others of the world's most famous peak. he is at home among mountaineers. his father was one of the first professional guides on everest,

and his brother has made the ascent 17 times. only two others have equaled his record of 21 climbs, and both have now retired. having said his prayers, he is returning to everest to try again in the middle of may when conditions are ideal. hundreds of climbers flock here trying to reach the roof of the world, but only rita can claim to have enjoyed the view so many times. brent: after a short break i will be back to take you through the day. stick around for that. ♪ [captioning performed by the national captioning institute, which is responsible for its caption content and accuracy. visit ncicap.org] q÷bi9y

- [narrator] for decades, the u.s. has been a leader in promoting global health. it does so through foreign aid designed to improve the welfare of others, as well as through emergency assistance to fight epidemics like zika and ebola. but foreign assistance has fallen out of favor with some in washington, who argue the u.s. should help itself before helping others. that puts them in confrontation with policy makers who say aid is a good strategy, keeping americans safe from epidemics at home and improving the health, economies, and security of neighbors abroad. does investing in global health improve america's security and other national interests? global health: preventing pandemic, next on great decisions. - [voiceover] great decisions is produced