why? was it to go after the -- to provide a diversion? was it to provide a means of escape? was it to attack folks who would be responding? we have seen that type of a tactic in war zones. and a big question is how would someone be able to get these weapons, put them together, assembly these bombs and use it tactically in this way? >> isn't it called the internet. >> exactly. law enforcement as they approach scenes like this, you never know what the capabilities of your adversary are. i think we have to anticipate that the people who perpetrate these types of incidence are going to have so much more knowledge. they are going in, not just a typical teenager, this is an individual bent on creating as much havoc as they can and may have some skills. >> darren, i want to get back to your fortification point. concentric rings of security.