LAWRENCE B. WILKERSON served as chief of staff to Secretary of State Colin L. Powell from 2002 to 2005. IN PRESIDENT BUSH'S first term, some of the most important decisions about U.S. national security — including vital decisions about postwar Iraq — were made by a secretive, little-known cabal. It was made up of a very small group of people led by Vice President Dick Cheney and Defense Secretary Donald Rumsfeld. When I first discussed this group in a speech last week at the New American Foundation in Washington, my comments caused a significant stir because I had been chief...