i can tell you generally, here's what you want to be able to do. you want to be able to question the person and then check what they are telling you against other information you're getting. if there are discrepancies, you go back and you challenge the person. the issue here isn't is somebody talking, it's whether they're giving you the whole story or whether they're concealing certain facts. that's why you can't treat interrogation as a fast thing. it's got to be something that takes place over a period of time so you can do the cross-checking that is a critical element in evaluating the truthfulness of what you're getting. >> let me go through some of the stuff that we have questions about. investigators right now looking into a theory that would link this attack to the pakistani taliban. if that were the case, this would be the first time that this group has struck against the united states. do you believe that they are behind this, given what we know? >> let me say, first of all, there's a tendency to treat these groups as if there's a