by Gary Hart

About the author: Gary Hart is a former Democratic senator from Colorado.

Should the United States have foreseen the seriousness of the terrorist threat and the real possibility that major symbolic targets, such as the World Trade Center and the Pentagon, would be attacked by terrorists using commercial airliners as guided missiles? Were there warnings and, if so, why were they not taken seriously? Why were rare early signals of danger disregarded by policy- makers and press alike? Most of all, what factors contributed to America’s dazed entry into the new and newly dangerous 21st century"

Historians and concerned citizens will be pondering these questions for decades, perhaps centuries, to come.

As early as 15 September 1999, almost exactly two years before the attacks, the United States Commission...