i have lived in the city for years, but hong kong still makes me fall in love with it time and again. >> and now, "bbc world news america." reporting from washington, i'm katty kay. apple asked a judge to reverse course on in order to unlock a terror suspect's phone, and the head of the fbi admits it is a very difficult issue. >> this is the hardest question i have seen in government, and it is going to require negotiation and conversation. stuck between greece and macedonia. as more nations shut their borders, thousands of migrants are left in limbo. in a new pop art exhibition opens in philadelphia, but even decades later, some of these images are still controversial. ♪ katty: welcome. apple has asked a judge to reverse an order of that the company -- an order that the company helped the fbi to unlock an iphone used by one of the san bernardino shooters. the original ruling created a firestorm in which law enforcement maintains it only applies to this one phone. apple argues that it requires greeting at back, which it refuses to do. reporter: the san bernardino killings in california before christmas, and the worst terror attack on u.s. soil since 9/11. in the shootout with police, a mobile phone was recovered, whose secrets the police are desperate to crack, to determine whether tosh fema leaked or syed farook have accomplices. the movement to do that -- -- alik leaked -- tashfin m or syed farook have accomplices. >> i love encryption, i love privacy. when i hear corporations say, we will take you to a world where people won't look at your stuff, i think that is great, but law enforcement, which i am a part of, really does save people's lives, and we do that through search warrants of mobile devices. reporter: at the moment, when the phone is locked, you have 10 attempts to enter a password, and after that all data on the device is a race. apple is being asked to write new software to disable that function, so the phone can be bombarded with every conceivable numerical password until one opens it. but last night, the head of as they can go. >> apple has cooperated with the fbi fully in this case. they came to us and asked us for all information we have on this phone, and we gave everything that we had, but this case is not about one phone. this case is about the future. what is at stake here is, can the government compel apple to believeftware that we will make hundreds of millions of customers vulnerable around the world, including the u.s.? there may not be another case like this. apple is reported to be working on a phone that is uncrackable. that may be a boon for privacy campaigners, less so for those whose job it is to investigate the activities of criminal and terrorists. this will be decided in the courts, not by a small band of protectors outside the fbi hq, so they are not an isolated minority. polls suggest americans are split down the middle on allowing the fbi do whatever it needs to, and the profound believe that some things, like he did on your phone, or none of the government does business. jon sopel, bbc news, washington. story, ifore this spoke with a "new york times" reporter who wrote today's article about apple trying to make it harder to hack in the phones. let's start there, matt, what is apple trying to do to make it virtually impossible for law enforcement to get into your phone or my phone? with the fbi is doing here is actually exploit a diagnostic mode that is built into every iphone. what that does, let's say your phone dies, or the software gets corrupted, apple has the ability -- with a up without new version of the operating system. what the justice department says is, great, just write us a version of the operating system with none of the security functions and booted up with that, and it turns out you can do that technologically without the user's password. from a fixing the phone standpoint, that makes perfect sense, but if you are thinkiig about the idea of apple making the government hack into its own phone, it becomes tricky, so apple is working on answering the question of, how can we keep the diagnostic functions on our phones so that if our phone software dies, we don't have to pay for a brand-new phone, but also make it so that apple cannot be forced to upload new software on your phone without their consent? katty: the ceo tim coates said this is all about the future. is this really about the future ofe customers, -- future customers, particularly millennials, who like privacy? >> i think it is more about the economy, and china being the largest market for iphones. it is definitely about the future. law enforcement evening knowledges that this is about the future. you saw the police commissioner in new york city come out and say, look, i have 175 phones i would like to do next after the fbi is dumb with there's, so it's not like this really is a one off, it is a one off in the sense of what they are asking for is one phone, but i think there is a recognition among law enforcement that if they will do it again. -- that if they get this authority, they will do it again. katty: but as i understand it, phone companies are authorized, but companies like google and apple are exempt. why? late 1990's,the when companies like at&t and verizon were moving to digital networks, the fbi became concerned that they would not be able to eavesdrop on phone calls with warrants, so congress, after much fighting, passed a law that says, if you are a phone company, you have to make your data available in real real,of listening -- in a plain, listening way to the justice department, and that has been the law of the land. google and apple are different. they are not phone companies, but they are also communication companies. this was just not envisioned by the law 20 years ago. and you said that director connie said this is the hardest decision he has seen in government. let's keep in mind that jim was involved in the decisions about wiretapping and waterboarding. this tells you how deeply divisive this issue is in the united states. katty: and around the world. thank you for joining us. greece has recalled its ambassador to austria amid tension of how eu member states are handling the migrant crisis. officials in athens are angry that they were excluded from the meeting on how to address the problem. austria and a number of balkan states have proposed their own border restrictions, which have left thousands of migrants stuck in greece. danny savage reports from the greece-macedonia border. reporter: pouring off the ferries at athens after landing on the beaches of the greek islands, in the last three days alone, 8000 migrants come to greece. this unstoppable flow of humanity can be found throughout the country. , a miles north of athens group of several hundred walk the last few miles to the border with macedonia. frustrated at having the way to cross. -- having to wait to cross. >> we have stayed in the camp for three days, and they do not let us go to the border. reporter: that's when they get here, to the overcrowded border camp. they will be out of luck. progress on the trail is at a virtual standstill. this is the one dates that migrants going from greece to macedonia have to pass through, but for much of the last few days, it has stayed shut. authorities say that is because the next border going north, between macedonia and serbia, is closed as well. it is the classic domino effect. borders further north close, so this one stayed shut too. border, the train was stuck for hours, and frustrations grew. so a backlog of coaches and communities is building up down the line. this is a service station just short of the border. greece is in danger of becoming a warehouse of souls, set a minister here today, and lots of them are little souls. there has been a sharp rise in the number of children on the move. these iraqi twins were born in turkey and have been traveling all their life. >> we have an concern for unaccompanied children, who at the moment, there is not sufficient baby care. reporter: now new cancer having to be open for them. the greek government is furious about decisions to restrict migrant flow. there is no agreement in brussels on what to do to tackle the situation. the intentions of some countries are obvious, though. the fear is that the migrant system is on the brink of total collapse. danny savage, bbc news, greece. president obama traveled to the u.s. state department for a meeting with his national security council, focused on the fight against the so-called islamic state. it comes on the eve of a scheduled truce in syria, which does not include the ongoing battle against isis. i spoke about the situation with the former supreme allied commander of nato, now the dean of the fletcher school at tufts university. migrants from the middle east into europe is not going to stop until the situation in syria is resolved. we have a cease-fire that is due to come into effect on friday. how much impact will it have? first of all, i am extremely peasant mystic that the cease-fire will actually take hold. themany of the big players, u.s., russia, the syrian opposition, etc. are friendly not in position to make this happen, but let's say it does come into play, i do not think it will have any effect because people on the ground will not believe it. katty: and the facc that al nusra, france, and the so-called islamic state are a part of this treaty, does that voided from the beginning? >> i think it does. the real hope on the ground is on imposed solution from the outside, much like in the balkans 20 years ago, but until the u.s. aad russia can come to , probably over the length of time assad will be allowed to remain, i think it is unlikely we will get to a solution. katty: is it just assad that is a sticking point for the white house, or is it a broader issue that even if they could agree on assad, this white house is so reluctant to get more militarily involved, that even safe zones are no-fly zones are nonstarters? about 80% ofsad is the challenge, but if we can get over him, the technical, military aspects of this, let's say, creating a safe zone in fighting troops to do that, that is an eminently accomplish double task. able task.ish katty: where were these troops come from? >> i would like to say local nations. jordan, turkey, iraq, nodding conceivable if we can tear down the islamic state in iraq. the saudi's have made noise about participating in this. it would have to be a u.s.-nato core of 5000 6000, but you could bolt on another thousand and create that kind of safe zone. katty: you describe a scenario that can work for safe zones, but the premise is agreement between the russians in the united states on the future of assad. ,o you think that the russians having launched their airstrikes , that they are coming around the idea that maybe they do have to play ball when it comes to assad in syria? i think so, particularly when oil prices continue to be so low. you are starting to see the bite of the sanctions in russia. i think we are at the point where there will be some level of give on the russian side. it will not be an on and on switch where suddenly the lights go on, hopefully it will be a little bit brighter. i think the thing that needs to be on the table at some point is a partition of syria. katty: which may happen. let me ask you about libya. we had the director of national intelligence speaking in congress today. he said he has great hope that there could be a government of national unity in libya soon. it is a big concern when it comes to the spread of the islamic state. with that make difference? >> it would make a huge difference. i agree with him. i think it is a possibility. you see a glimmer of hope. ironically, the presence of the islamic state is what is mobilizing that. neither the groups in the east nor the groups in the west, particularly general half dollars forces in -- general , want to seeces the islamic state dig in. if we, the west, can find partners on the ground in that regard, i think we have a shot at bringing libya back from the brink. katty: thank you so much for coming in. and some other global news, an independent inquiry has concluded that serious failings at the bbc allowed the former tosenter jimmy sample sexually abuse victims undetected over a period of decades. the investigation identified 72 him.e abuse at the bbc by the report says there was a culture of reverence and fear towards celebrities. at least three south african universities have been closed following violen student protest. been clasheslso between black and white students, including a war on a rugby pitch. students are pressed -- are protesting tuition fees and the use of afrikaans language. our road trip continues in arkansas, where someday members of the community gayome day members -- members of the community still struggle to be accepted. the flying scotsman has made its historic return to the tracks. mr. -- richard wescott was on board. reporter: it is not a local motive, it is -- locomotive, it is a celebrity. the flying scotsman comes back to it. and ground, eating up the miles. it is a rewarding job. this is one of the things that makes the train unique in the world. the drivers could change over while the train was still moving, and that made the service that went from london to scotland nonstop. has had the ups and downs of a celebrity's life, taken out of service in the 1960's, shipped to the united states, shipped to australia. it has been in the workshop for years. many people believed that it would never again rumbled these tracks. flying scotsman has always made headlines. it was the first train officially call that 100 miles per hour. arey, the only delays without transponders on the line. the crew are starved for the day. the enthusiasm is high. >> it is great to see everybody supporting the engine. decade out ofr a the limelight, flying scotsman is going to be touring again, so thousands more can revel in this site. sight.ts ♪ here in the u.s., the five remaining republican candidates will square off tonight in their final debate before super tuesday. they all want to appeal to voters in the 11 states due to vote next week. this election comes amid a backdrop of a deeply divided nation, not just on political issues, but social ones too. on part of our continuing road top, regina went to arkansas meet lgbt americans that say discrimination is a major problem. ♪ >> they don't care about caitlyn jenner. they believe about what their interpretation of the bible is, and they unfortunately oftennuse that to justify kicking their child out of the home. >> i have been punished, i have been hated. i've got things thrown at me. arkansas is the heart of america's bible belt, where faith comes first. homosexuality is incompatible with their religious beliefs. and those beliefs have been routed, which means that the change that has been seen and felt in other parts of america has not quite reached year. he dreams of becoming a chef. he was a teenager when he came out to his mother, who failed to accept his sexuality. he ran away from home several times before finally getting his own place in low income housing. >> my mom, i felt she did not agreed it a religion -- agree do religion.n -- due to she even mentioned in the bible, it says day is a sin. is a sin. katty: howdy you feel when you go to church? >> i feel that i go there to lord.he word of the i don't go to hear what people say. people used to tell me, it's a demon, and i was like, no, because i presently know that is not true. ♪ reporter: penelope poppers runs lucy's place, which helped kaelin find a place to live. it is the only center of its kind in arkansas. it is said that many shelters run by the church turn lgbt people away. >> we had made all these and adults are feeling more empowered to come out, but their parents in little rock, arkansas, where these very small towns, they have not , anded, they are the same they still believe that lgbt people are less than or do not deserve it. reporter: there has been a generational shift in attitudes toward lgbt writes, but in some parts of america, these views remain entrenched. katty: now, think of pop art and andy world halls -- pop art and andy warhol's marilyn monroe might spring to mind. these artists were exploring notions of celebrity and sex to produce work that was bold and subversive. pop art was also a global movement, as then exhibition at the philadelphia museum of art makes clear. some of these images are still attracting controversy. copart first onto the scene in the late 1950's and swept the globe. it was commercial, subversive, youthful, witty, and sexy. fact, that this image of a woman licking ice cream cone was censored by facebook just a couple of weeks the philadelphia museum of art used it to advertise this exhibition. >> i think it was surprising, but it was also a great reminder of how shocking this work can still be, and how relevant it is. thatf the great debates happen on facebook and instagram and all of our different social media feeds was why this image would be so troubling to some people, or not troubling to other people. reporter: sex, of course, still sells, but the pop art was when it first became commercialized, and a heady brew of consumerism and sensation. confined towas not the u.s. or britain, where it had its roots, this was an international movement. >> these artists were grappling with the new reality around them, and representing it in their work. reporter: these panels were created by brazilian artists in the 1960's when the country was experiencing a lot about people. they are a comment on censorship violence.rtrayal of these images were censored in the newspaper. the artists, however, has given up the ability to uncover them. 87 artists are represented in this exhibition, and no many of -- and though many of these works are half a century old, they remain exuberant and provocative as the day they first popped onto the scene. katty: love that. before we go, there is one last story that we wanted to share with you. a young afghan boy had his picture go viral when he improvised a lionel messi shirt made from a plastic bag. now, he has the real thing. the five-year-old received a -- signed jersey. unicef has posted a picture of him proudly wearing it, and even scoring a goal in it. the afghan football association says it plans to set up a meeting between the boy and messy. -- and messi. we will bring you that news, and pictures, as soon as we get them. that does it for our news. if you would like to reach the bbc team, you can find us on twitter. this has been "bbc world news america." x for watching. we will see you again tomorrow. ♪ ♪ >> make sense of international news at bbc.com/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 nnglected 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 moments unforgettable. i have lived in the city for years, but hong kong still makes me fall in love with it time and again. >> "bbc world news" was presented by kcet los angeles. hi. it's me--coach hooper-- and i've got my special whistle, which means it's time to get up and exercise! [bird caw] wow! it's also time to get a new whistle. ok, now, let's get moving because today, we're going to exercise like race car drivers. ♪ head towards the track ♪ towards the crowds and your car ♪ ♪ it's almost time to start the race ♪ ♪ so keep up the pace ♪ now race that car ♪ turn that wheel just like this ♪ ♪ vroom vroom ♪ all right! ♪ and do the victory jump ♪ jump on up, yeah! ♪ you're a winner, woo hoo! ♪ ♪ do the victory jump awesome job! and if you want to try out more exercises with me, just visit pbskids.org anytime you want.