Reply #6: Yes, that's the building I mentioned.

[dailykoff]

The short structure in Mexico (21 floors) that looks like it had a concrete frame. Look carefully at the lower levels.

In any case, notice that the collapse is not in fact "total," and that the bulk of the structure appears to have rotated off its base and fallen 90 degrees, more or less intact, like a tree.

The conservation of angular momentum tells us that rigid structures that begin such rotations--like the top sections of the Trade Center towers--will do exactly that, not disintegrate in midair like fireworks.