christof putzel has more. >> reporter: the boston public library. york's grand central terminal. the national history museum in washington, d.c. these iconic buildings have a secret, but to discover what it is, you have to look up. these vaulted ceilings and domes were designed by a father and son team of masons. >> it's almost as many they were dropped here from the 14th century into early 20th century u.s. building some of the greatest buildings our country has ever known. this is really an immigrant's story of the unnamed, talented, master craftsmen who made our country and made our great buildings possible, but who haven't really been celebrated. >> reporter: in 1881, raphael and his son migrated to the u.s. from barcelona, bringing with them an old world masonry technique. >> the method was absolutely revolutionary in its day for three big reasons, it was fireproof, incredibly strong, and could be built with no support from below during construction. almost like magic. and just look at how thin this stone is, because it's unbelievably thin. it'

christof putzel, al jazeera, new york. >> that's it for tonight, we'll have more of "america tonight," tomorrow. vitaly churkin >> the major developments in the ukraine have worldwide implications. russia's black sea fleet ordering them to surrender by monday. the commander threatened a real assault of ukraine's military if the deadline passed. a fleet spokesman claimed there were no immediate plans for a russian attack. meanwhile ukraine's u.n. ambassador said monday that russia put 16,000 troops in crimea for the past week. sergei lavrov, the forin minister, in geneva said russia was protecting its interest and russian's citizens that lived in ukraine: >> russia's u.n. ambassador insisted troops in crimea were invited, entering at the request of deposed ukrainian president viktor yanukovych to establish: >> but america's u.n. ambassador samantha power didn't buy it. >> military action cannot be justified on the basis of threats that haven't been made and aren't being carried out. there is no evidence that ethnic russians are in danger. >> meanwhile at the white house president obama

"america tonight"'s "america tonight"'s christof putzel reports. >> if the sinaloa cart was, built a massive empire worth more than $3 billion a queer. jack riley runs the dea's field office in chicago. makes it the perfect place from moving drugs from mexico to cities across the united states. >> from my point of view i think chicago and the midwest in general right now is the most significant hub for the cartels in the country. >> chicago's gang culture also makes it a recruiting ground. with tens of thousands of active armed drug members ton streets, drugs are easy to come by. >> what do you sell? >> crack, dope, x, if it's there we're going to sell it. >> what do you have here? >> crack. >> that's crack? >> west side of chicago, the last ling in the sinaloa supply chain. >> where do the drugs come from? >> mexico, columbia. they are the one who bring it. this is our job. this is how we eat. this is how we feed our families every day. >> does it ever concern you that you might be selling a product that might be hurting people? good >> survival of the fittest right. >> they are not

christof putzel reports, they worry about their home land but also the family and friends that are still there. >> it is a chilly friday night in manhattan's east village. these these ukrainians are mix ing mixing drinks with politics. working to support ukrainian nationalism from abroad. >> we are together because we want to help because we care. >> that sense of community isn't hard to find in the east village. tens of thousands of ukrainians live here earning it the nickname, little ukraine. >> you are always attracted to that culture and you seek it out. i've been here for ten years but there have been people here for 60 years and they still stay here as a community and they still seek out all the ukrainians in the city. >> that sense of nationalism led maria home in december to join tens of thousands of protesters in the capitol's independence square. >> standing there with half a million people singing your national anthem and being proud of who they are and fighting for the truth. there's nothing, there's nothing else that can ever give me that feeling. >> irina started bartending