Buildings mined

Has anyone out there heard that buildings that house Govt. offices of NSA, CIA, NSC etc. are routinely mined with explosive charges to bring them down if their security is compromised as in time of war, to keep sensitive and.classified information out of the hands of an enemy? I heard that speculation several times. I believe that all three buildings in the WTC complex did have Govt. offices in them. Would the fires have set them off, or would someone have set them off on purpose. It's an interesting question, and the answers would probably be even more interesting.

who would insure that building?

I don't think so. I posed this question to Steve Jones a while back (I'm a student at BYU) and he answered that no insurance company in their right minds would insure a building that had explosives in them waiting to go off. All it would take is a small fire or a confused electrician for one of those babies to go off.

In WWII they used to line

In WWII they used to line the rebar in concrete that was used for submarine bases with explosive powder. This was so they could be demolished if overrun. This is though, the only documented case of this Ive heard of personaly.