else may be in his orbit. >> exactly. good news is, digital footprints don't go away. in the first instance in the near term the focus has to be on making sure there are no other attacks planned. so law enforcement intelligence officials can look at his digital footprint and say who else was he in touch with, was he urging anyone else to take similar action. at the same time we can use technology as force for good here. we can go back and use advanced machine learning tools to say, what was the suspect's pattern of behavior on-line and then look to see whether any other users are exhibiting similar patterns and that can help ward off attacks. >> so that's the key is preventing the next one or deterrence as well. shameus, you have researched dozens of homegrown terrorist cases. they believe the attacker was radicalized during his time in the u.s. not before. based on what he's telling investigators apparently, what they found on his phone and vehicle, what do you take away