One of the articles I've read indicated that the beams were asbestos insullated.... up to the 64th floor, when the asbestos scare set in and they switched to another insulator.

There is some chance that if the entire structure's metal had been insulated with the asbestos sheathing used for the lower 64 floors (the sheathing process used, BTW, has never been found to be harmful), perhaps the towers would have endured another couple hours. Or maybe even survived, who knows?

Note that first strike hit higher - lasted longer.

But the second strike hit more viciously; if you see the replays (as you probably have), that fireball and debris cascading out the other side of the building was worse than happened with the first building. I don't remember seeing an "exit wound" from the first strike. (But I was at work at the time and was not able to see much coverage; we had a television set in a conference room, but I only saw bits and pieces.) And the second strike certainly had fire crawling down the sides of the building, unlike the first one where it seemed confined to the upper floors.

I think your thought is predicated on an invalid assumption, anyway - there's no way to know at the moment whether the terrorists even imagined they would bring down the entire complex. Massive damage and loss of life, sure, they wanted and expected that. Terror from terrible fires, yes. But to bring the entire thing down? I've seen the report from the professor in England who knew it was "inevitable" that the towers would collapse, but he seems to be the only one on the Web who claims to have known in advance.

Perhaps they were hoping the towers would fall over (imagine the top of a tower falling over two or three blocks! ow!). But I suppose we won't know unless/until we catch and interrogate one of the designers of the scheme.
I base some of my thinking about the scope of the expected damage from their strike on the Pentagon. If they had expected a Trade Tower collapse type of thing, surely they would have found a richer target than the Puzzle Palace.

By the way, I've read and heard several reports about some of the other buildings buckling and perhaps collapsing themselves but other than building 7, I've not been able to find any reports about what exactly is down, damaged, or decrepid. Anyone have links?

And that advice would have told them the towers were designed to absorb airplane impacts.


On the other hand, perhaps they had someone like this England professor on their payroll. As yet, nobody knows.