Had a thought, as I sometimes do. What if DC was the only escape left for the evil fuckers after all the other escape routes have been blocked or blown up? I think the fences, concertina wire, and soldiers are meant to stop any bastards from escaping when they try to come to the surface and run. I think this is what's going on. DC is the only way out and the military is waiting for them to either suicide, get killed by soldiers, or surrender. Maybe that's what's holding things up now are the last stubborn fuckers who have cornered themselves underground and it's now a stand-off. Maybe the most important asshole in the underground is now cornered and has only one way out. If they are in possession of some kind of weapon that would kill both them and anyone else in the tunnels, it really would be a waiting game. My .02 cents.