Age: 54
Occupation: President of Afghanistan
Karzai has big problems: he commands limited credible force or political support of his own, and his power depends on a U.S. presence that will end in 2014, and on which much of the Afghan population has soured. The Taliban, meanwhile, has momentum, patience and a declining incentive to compromise. That leaves Karzai caught between challenging the U.S. to burnish his nationalist credentials and working to block any U.S.-Taliban rapprochement in which he is sidelined.