NEW YORK - The 1993 World Trade Center bombing left a giant crater in the basement of the 110-story twin towers and an even larger hole in the nation's sense of security. With the 15th anniversary approaching, the days before the bomb blast appear to mark the last time when millions of Americans went about their business, unaware of the dangers posed by international terrorism. "Not an awful lot of people thought about how vulnerable we were," recalled Joseph Guccione, the U.S. marshal for New York. "It was a terrible lesson that was learned." Lower Manhattan tried to armor itself...