Jon D. Magnusson, chairman-CEO of Seattle-based

Skilling Ward Magnusson Barkshire Inc., one of the

successor firms to the engineer of record for the

World Trade Center, Skilling Helle Christiansen and

Robertson, says that in the dozens of media interviews

since the attacks, he is asked the same question: Why

did the towers collapse? He says he answers a

different question: How come they stood up so long?

Ninety-nine percent of all buildings would have

collapsed immediately had they been hit by a Boeing

767, says Magnusson. "The real question is how did

they stand up so long after the planes hit?" he says.

That provided precious time that gave occupants time

to escape. The answer, he says, is the redundancy

inherent in the design of the exterior structural tube

designed by Les Robertson and the late John Skilling.

The time between the attacks and the collapses

saved thousands of lives, he adds. "You can't harden

these buildings to take that kind of impact," says

Magnusson. "If you design for a 767, what about a 747

or an Airbus super jumbo?

"It's a losing proposition," he continues. "Even

if you could harden the buildings, with the awareness

that airplanes can be used as weapons, what about [the

vulnerability] of people at football games, in

cathedrals, in concert halls? The problem is not about

buildings. The real question is how do you keep

airplanes out of the hands of evil people? As we enter

this national dialogue, we need to make sure we're

focusing on the right problem."