Quivering Heights.(Brief Article)

From New York to Shanghai, cities have raced for decades to erect the world's tallest skyscrapers. Structures like Chicago's 443-meter-tall Sears Tower or Kuala Lumpur's 452-meter-high Petronas twins have served as powerful totems, shouting out economic arrival. "The skyscraper," says Robert Stern, dean of the Yale School of Architecture, "is the symbol of success." But when two passenger planes smashed into the World Trade Center on Sept. 11, that equation was forever altered. Skyscrapers were suddenly transformed into fragile deathtraps. "Right now it's hard to justify building such huge monuments," says noted New York-based architect Shoji Sadao. "They are just too tempting a target."

Giant skyscrapers may turn out to be among the first casualties of the first war of the 21st century. Ever since the 50-story Woolworth Building was erected in lower Manhattan in 1913, a debate has raged among architects over the safety and practicality of the supertall building. Now those who have long agitated against them have suddenly found an attentive audience. "The days of competing over who has the tallest building are over," Japanese architect Toyo Ito declared last week. "The World Trade Center attack has taught us something that I've always believed: human beings should live closer to the earth."

Skyscrapers have always been more about ego than economics. A building more than 80 stories high requires steel reinforcements as bracing against the wind and extra elevator banks, which limit the amount of office space--and cut into profits. Only now have critics' worst suspicions been confirmed: the sheer height of these structures makes them potentially devastating hazards. The World Trade Center withstood the initial blow of two terrorist-driven Boeing 767s. But the jet-fuel fire melted its steel girders into putty, dropping acre-size floors onto each other like a lethal stack of metal pancakes. Firefighters couldn't reach upper floors in time to be effective. "It's morally wrong to build those kinds of supertall buildings now," says British architect Mark Dytham. "Nobody knows how to cope with that kind of fire at that kind of height."

Yet there's plenty to be said for the supertall building. For huge companies, they allow thousands to work together. Views from the windows feed executive egos. In crowded cities like Hong Kong, high- rises leave room for much-needed parkland. Some architects contend that the World Trade Center's collapse was actually a testament to its ...