Before Sept. 11, 2001, the Pentagon building seemed to be the safest place imaginable — a well-guarded stone fortress that symbolized American military might. Judy Scott, an administrative assistant for the Department of the Army, was in her Pentagon office that morning when she received a call from her sister in Arizona. Carolyn Mann had just seen a news report about the plane flying into one of the World Trade Center towers in New York City, and she called in agitation to make sure Scott was all right.