Andy writes:

Other large skyscrapers survived massive fires, while the WTC collapsed. Why? The other skyscrapers were privately built with superior construction, while the WTC was a government building built by politicians and the product of regulatory hysteria about asbestos. The NY Times says:

A 1988 high-rise fire in Los Angeles sounded another prescient alarm. Flames from the blaze at the 62-story First Interstate Bank building, then the tallest tower west of the Sears Tower in Chicago, lapped up the side of the building, gutting offices from the 12th to the 16th floor. By all accounts, the response was fast and well organized, as firefighters quickly eliminated a water-supply problem by linking mobile pumpers into the building's system.

The fire burned for three and a half hours, killing a maintenance worker and injuring 35 others.Engineers later discovered that the building survived the fire with surprisingly limited structural damage; credit was given to especially thick layers of a relatively heavy, cementlike fireproofing that had been applied to structural steel. The World Trade Center had the much lighter, easily dislodged fireproofing on the floor braces whose failure probably initiated the collapse.

No modern fire strikes as strong a resonance with the trade center as the 19-hour, eight-floor fire at 1 Meridian Plaza in Philadelphia. Three firefighters died, few compared with the 343 firefighters who died at the World Trade Center.

Here's an article that claims, mistakenly I think, that extra explosives must have brought down the WTC. "Fire has never caused a steel building to collapse," Hufschmid writes, "so, how did a 56-minute fire bring down a steel building as strong as the South Tower?"