i see them as a valuable s pekt of the multiple layers of security and even if they are not air marshals on a particular flight and we assign them on a risk-based model also, there is a turn up effect. we know terrorists are aware that we have air marshals here in the u.s. and they see that as a deterrent. we are fortunate to have a number of pilots and the program. so even if there is not an air marshal on board, it is possible there will be a pilot and if they tried to get in the pilot, they will have an opportunity to defeat the terrorist. >> do you think that the see something say something campaign is working? >> i think it's a lot of common sense. i think it's something that we saw with the times square bomber and he saw something suspicious and reported it. that's just incumbent upon all the us to say if there is something that seems out of whack and i have concerns about this person or this event as much, it makes sense to let the authorities look into it and resolve the concerns. as far as identifying the terrorists, i know from my fbi experience a number of investigations were

the two leaders beings pekted to talk about the upcoming nato and g-8 summit, the middle east, iran, the global economy. you're looking at live pictures of the opening ceremonies on the south lawn of the white house. you see joe biden and his wife jill greeting the british prime minister and his wife. the two national anthems will play, one for the u.k., the other from the united states. then i think in just about an hour the president and the prime minister will make some remarks to the press. before we get to all of that let's head to washington and talk to brianna keilar. she is there on the south lawn of the white house. describe the scene for us. >> reporter: carol, what you're witnessing is very much the formality of the day. this welcome for this official visit by prime minister david cameron. yesterday it was more informal as the prime minister and the president took in an ncaa basketball game in ohio. today it's all about the pomp and circumstance. the prime minister will be receiving really quite the red carpet treatment as you can already see. there will be a 19-gun salute