He is clearly not a pacifist, though he was elected on a pledge to end the Iraq War, and he did.
But he also sent men to kill bin Laden. He helped engineer the international campaign that ended the life and regime of Libya's Moammar Gadhafi. He decimated the leadership of al-Qaida, cutting them down from above with a drove of drones.
And he escalated the war in Afghanistan, threading the needle between generals who wanted an even larger force and his own vice president, Joe Biden, who wanted to pull troops out. In his book, "Obama's Wars," Bob Woodward describes a president who is deeply involved in planning, one who recoiled when military leaders tried to convince him that his only real option was to send 40,000 troops with an open-ended commitment.
"I'm not going to make a commitment that leaves my successor with more troops than I inherited in Afghanistan," Obama said.