Donald Rumsfeld, the two-time US defence secretary and one-time presidential candidate, has died at the age of 88, his family said in a statement.
He was regarded by former colleagues as smart and combative, patriotic and politically cunning, and had a storied career under four presidents and nearly a quarter of a century in corporate America.
But his reputation as a skilled bureaucrat and visionary of a modern US military was soiled by the long and costly Iraq war.
In 2001 he began his second tour as Pentagon chief under George W Bush, but his plan to “transform” the armed forces was overshadowed by the September 11 terrorist attacks.
He oversaw the US invasion of Afghanistan and the 2003 overthrow of Saddam Hussein in Iraq, where he was blamed for setbacks including the Abu Ghraib prisoner abuse scandal and for being slow to recognise a violent insurgency.