Age: 50
Occupation: U.S. President
After three years in office, Obama has transformed from an inspirational figure with a thin résumé into the nation's gray-haired steward. He has put distance between the U.S. and the Iraq war even as events like the alleged massacre of 16 civilians by a U.S. service member complicate the 10-year quagmire in Afghanistan. He has faced down Iran with sanctions and congressional Republicans with scoldings. But a fragile economic recovery threatens his re-election prospects and an even lengthier résumé.