Engineer Defends Fallen Towers

...Mr. Robertson began his review by flicking through slides of prefabricated exterior panels being hoisted into place in the early 1970s. Gripping the lectern, he faltered. "Oh boy," he said, bowing his head. He gathered himself. "Next slide."

He used a laser pointer to highlight grim photos of Ground Zero: exterior panels torn into jagged sections, twisted steel columns, towering piles of rubble. The commentary continued, like a medical examiner detailing an autopsy. "Here you see classical tension failure. Next slide. You can see the columns displaced. Welds are sheared off. Classical failures. Next slide."

Then came the question-and-answer period. "Is there anything you wish you had done differently in the design of the building?" one engineer called out abruptly. The room fell silent. Mr. Robertson paused and scratched his head. "I guess I wish I had made it stand up" longer, he said, his voice trailing off. "I mean, every man was important . . . " He stood alone at the lectern and wept....