in place in order to kill innocent people on behalf after foreign terrorist organization. >> san bernardino involved two killers who were radicalized for quite a long time before their attack, as early as the end of 2013, they were talking to each other about jihad and martyr dom before they became engaged, married, and lived together in the united states. we are working hard to understand exactly the source of their inspiration and whether or not there was anybody else involved with assisting them, with supporting them, with equipping them. you pay us to do counterterrorism. we are not perfect. we are good at this. we cannot allow ourselves to be paralyzed by what these people are hoping to eye chief. that's what i hope the american people will take from the unsettling experience of watching what is going on between san bernardino and paris. >> our chief intelligence correspondent katherine herrage