But as vice president, Biden is taking credit for success in Iraq.
"I am very optimistic about Iraq," he said. "I mean, this could be one of the great achievements of this administration."
But Republican Sen. Jim Inhofe of Oklahoma, a member of the Armed Services Committee, said you cannot oppose the surge and then claim it for your legacy.
"When Joe Biden was in the Senate and Obama was in the Senate, they authored and were the chief architect of the resolution opposing the surge," he said.
The vice president also took credit for the troop drawdown.
"You're going to see 90,000 American troops come marching home by the end of the summer," he said. "You're going to see a stable government in Iraq that is actually moving toward a representative government."
But the drawdown was negotiated in the Status of Forces Agreement before the Obama administration took office.
"The reduction in U.S. forces that is under way right now is in fact important and it's largely the continuation of the policy that President Bush had set in place when he negotiated the drawdown schedule with Prime Minister Maliki at the end of 2008," Michael O'Hanlon of the Brookings Institution told Fox News.
In fact, the agreement called for having U.S. troops out of Iraqi cities by June 30, 2009, and all U.S. combat troops out by the end of 2011.
"The timetable for withdrawing those troops had been worked on for a long time, way preceding this administration coming into power, and that timetable really centered on success in Iraq," said Col. Bill Cowan, a Fox News contributor. "That success starting really after the surge that was implemented by the previous administration."
"Well, putting what was broken back together and getting our troops home, which we intend to do in August of this year," he said, adding that Obama helped provide critical "political pressure" on Iraq policy before taking office.
Experts, noting a peaceful transfer of power is a key step for a young democracy, suggest another major test for Iraq is coming up March 7, when provincial elections are scheduled to be held.