I don't want to seem patronizing towards anyone, but I've noticed something.

A lot of these "home grown" terrorists appear to have gotten their understanding of physics and explosions from Hollywood. Gas/petrol doesn't actually explode very easily. Only the vapor explodes and it has to disperse quite a bit first. I have a feeling that this fools thought that if the car was on fire and got splashed with more gas/petrol that it would burst into flames like in the movies. Thank God it doesn't actually work like that.

I guess in some ways we're lucky that the educational system isn't all that great. At least these guys never really learned what would really cause a big explosion.