knew beforehand? >> well, one of the things you have to concern yourself with, too, from not an intelligence standpoint, alisyn, but an operator standpoint. i was involved in an action in 2012 against a terrorist cell in frankfurt and what happens is you know the intelligence coming in. you see the operators. you may not have enough information yet to arrest them because they haven't done anything wrong but the other thing is, as the chief operator you have to balance whether you strike and get a large target, or strike and just get one individual. so perhaps there was more intelligence being kwleened that would lead to a bigger network, to an unraveling of the network. and that's always a consideration when you're going after targets. so, sometimes you say, why didn't we get this one guy? >> yeah. >> where the answer would be, well because we were hoping he would lead us to a cell of 100. and sometimes you miss it. >> phil, very quickly, in the u.s., when people have information, when authorities have information that somebody is trying -- thinking about planning a christmas market attack, what happens?