From the AP:

The United States did not have enough troops in Iraq after ousting Saddam Hussein and "paid a big price" for it, says the former head of the U.S. occupation there.

L. Paul Bremer said Monday that he arrived in Iraq on May 6, 2003 to find "horrid" looting and a very unstable situation.

"We paid a big price for not stopping it because it established an atmosphere of lawlessness..."

In later remarks he appears to backpeddle a bit and complain that his comments were meant to be kept private.

See also "How you fail the global test".