How 9/11 Changed Skyscraper Design
September 11, 2001, changed our lives. A lot. Political differences seemed to disappear, at least briefly. New security measures filled the world's airports. Thousands of families mourned the loss of loved ones. And, of course, the New York City skyline lacked its two tallest buildings. But there's one change that you probably didn't notice, because it took place inside new high-rise buildings. And it's probably not what you're expecting.