Robert Strange McNamara
January 21, 1961 - February 29, 1968

He mishandled the Viet Nam war,
and has admitted the war was a mistake.
The Fog of War.

wikipedia

Donald Henry Rumsfeld
January 20, 2001 - December 18, 2006

He mishandled the Iraq war.
Has yet to admit the war was a mistake.

wikipedia