Just wanted to make a case in point about the lack of a crater...
Anyone remember the Mythbuster's episode with the cement truck? When they set off something on the order of 5,000 lbs of explosives in it? Took about .001 seconds for there to be no truck left. No crater. IN fact, not even a scorch mark, really. Within a few weeks, you wouldn't be able to tell anything went off there.
Explosive blasts are fluid, to a degree. The force will follow the path of least resistence, preferentially. Take a fire-cracker. Light it. Place it on top of an empty soda can. Doesn't do much. Place the same firecracker inside the can. Set it off. Observe the results.
The ground is a lot stronger then the building. The ground (and the chassis of the truck) actually redirected parts of the force upwards, back at the objects around the sides (such as the building). The ground can withstand a 10,000 force acting on it pretty easily. Very few buildings are designed to withstand such a force when it's applied laterally.
You need to quit getting your information on explosives from Rambo movies and prime-time TV. I've worked with explosives of all sorts (from C-4 to C-B, from black powder to TNT, from ANFO to AN-AL, from anti-personnel mines to anti-tank mines, from 1lb. shaped charges to 10,000 lbs. mass charges, and from mortar rounds to missiles). I've seen real explosives detonated, and been involved in doing the detonating. I've been present when tons (literal tons) of explosives where detonated in the destruction of material from Iraqi ammunition depots. You have no knowledge of the subject on which you pontificate.
The less one has to say, the louder and more often they seem to say it.