The Ocean's Eleven actor has become a leading celebrity advocate for an array of international issues in recent years, including drawing attention to the plight of Sudanese refugees desperate for an end to decades of civil war.
Clooney's continued interests away from Hollywood have sparked speculation he will one day quit movies for U.S. politics - but the 49 year old is adamant his past personal antics will cause problems for any campaign organisers.
He tells Newsweek magazine, "I didn't live my life in the right way for politics, you know. I f**ked too many chicks and did too many drugs, and that's the truth."
The actor insists a life in politics is not on his mind just now, although he'd come clean about everything if he ever did decide to run for office.
He says, "(I'd) start from the beginning by saying, 'I did it all. I drank the bong water. Now let's talk about issues.' That's gonna be my campaign slogan: 'I drank the bong water.'"