AGE: 57
OCCUPATION: International Security Assistance Force commander
PREVIOUS APPEARANCES ON THE TIME 100: 0
PRO: The top U.S. commander in Afghanistan, McKiernan must develop a strategy of engagement in a region where the Taliban is taking over, with suicide bombings and small-arms attacks on the rise.
CON: According to McKiernan, the 17,000 troop increase approved by Obama isn't enough. And the attempt to tame Afghanistan has already felled one superpower.