Since September 11, 2001, Seymour M. Hersh has riveted readers -- and outraged the Bush Administration -- with his explosive stories in The New Yorker, including his headline-making pieces on the abuse of prisoners at Abu Ghraib. Now, Hersh brings together what he has learned, along with new reporting, to answer the critical question of the last four years: How did America get from the clear morning when two planes crashed into the World Trade Center to a divisive and dirty war in Iraq?

In Chain of Command, Hersh takes an unflinching look...