andrew, what does this say to you, though, about the person who did this? obviously it could be people that did this, that there was no tip. you as a lone wolf happen and it could get through the cracks, but does this show a person who doesn't interact with a lot of people, that they might have been a loner, that there wasn't a lot of tips? >> we absolutely don't know if this is a domestic attack or if it's foreign. one thing i can tell you is that they have kind of a cynicism about trying to put together a plot involving several people. one of the members of the radical far right told me a couple years ago in our movement being an informant or ratting out your friends is pretty much a career path. so there is a great deal of suspicion. there is a tendency to believe that if you do it yourself, there is a chance that it will succeed. if you do it with others, almost certainly the plot will get rumbled. so if it is somebody from the radical far right, that may well be their thinking. they were devastating devices that detonated, but they were relatively simple to make, unlike the oklahoma city bomb which was very big, very devastating, there