. >> mike chertoff, look, this is a primal fear anybody has, you're on an airplane that goes down ort vanishes. it may sound like a naive question but in this age when we can find our iphone with gps, how do we lose sight after aircraft? >> one of the questions is whether the malaysians were forthcoming what they saw in terms of radar or whether they held back information. so part of the problem is i think there was a scarcity of information at the beginning and there may have been some misinformation, perhaps, inadvertent. that's made it more difficult. >> what do you worry about now? there's a scenario that took place that we're trying to piece together. after 9/11 when we thought so much about aviation security, are there any things we need to learn from here? >> i think there are. one of the theories is one or more of the pilots may have been involved in this. of course, much of our screening has been focused on passengers. increasingly we face the question of inside threats. what do you do when people who are working in an organization or an enterprise become a problem? it could

our audience will recognize as a longtime aviation correspondent for nbc, joining me along with mike chertoff to talk about what this debris means. are they closer to the real trove of what would be the wreckage? they are up against the clock here because they've got this, you know, the black box that will only last for so long here, and without finding that, you run the risk of not finding, you know, what happened. so, that's the real concern here, even as there are real security questions. >> and another story that we're following closely is the ukraine conflict. >> yeah. >> and we know u.s./russian relations obviously not at its best. what more can the white house do at this point? because it seems like putin is really determined to stand his ground. >> well, he is, and i think part of -- the question is, what does it take for the u.s. to get the upper hand again here? because putin does seem to be in control. economic sanctions that really hurt is one option, but there is also a real fear that putin's not done with crimea, that he might push into eastern ukraine. that's not a nato member.