Could the [9/11] bombers have been stopped? NEWSWEEK has learned that while U.S. intelligence received no specific warning, the state of alert had been high during the past two weeks, and a particularly urgent warning may have been received the night before the [9/11] attacks, causing some top Pentagon brass to cancel a trip. Why that same information was not available to the 266 people who died aboard the four hijacked commercial aircraft may become a hot topic on the Hill.