>> evidence of a you tube page that may connect to the older brother. the younger brother there's very thin evidence of anything. >> on the elder brother, tamerlan's you tube channel there's an equal number of rap videos. i don't know why we tend to focus on this one particular aspect because they have a lot of consonants in their name but in lots of other context we go to other kind of motivation. we really ought to look at those. >> there's a history of terrorism being used as a military tactic. has there ever been an american target on a target outside of russian federation for chechen