A powerful actor known equally for his off-screen volatility and his on-camera intensity, Penn has staked out a position along, and sometimes over, the left flank of the political debate.
Abroad, he has visited Iran and Cuba and befriended Venezuela's Hugo Chavez; at home, he has been more likely to show up with Ralph Nader than with mainstream Democrats. Penn's causes have ranged from opposition to the 2003 Iraq invasion to support for gay rights.
Penn's influence, though, has come less from his vanguard political pronouncements than from the example he has set through his personal engagement with gritty challenges. He joined reconstruction efforts after Hurricane Katrina and established a relief organization in the wake of the 2010 Haiti earthquake, eventually enlisting as the manager of a refugee camp serving thousands of displaced people.
Through such efforts, Penn has helped to set a modern model for Hollywood activism that prizes direct action over lobbying Congress or embellishing campaign rallies. He has demonstrated that the best way to get in the door on Capitol Hill is to arrive with mud on your shoes.
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