Senate Foreign Relations Committee Chairman John Kerry (D-Mass.) on Sunday gave a firm defense of the U.S. mission in Afghanistan, rejecting any comparison to the Vietnam War, in which he served.

Speaking on NBC's "Meet the Press" to host David Gregory, Kerry said the Obama administration has acted correctly in continuing the war in Afghanistan and should be able to withdraw troops as planned in 2014. Gregory had played Kerry a video clip of his 1971 testimony before Congress in which Kerry famously called the Vietnam War "a mistake."

"In my judgement, Afghanistan is just not Vietnam," Kerry said. "We shouldn't have been in Vietnam. It was a surrogate war, it was a cold war. There are any number of reasons it was a gigantic mistake. In Afghanistan, we're there for a purpose. I don't believe the size of the footprint we have doing everything we're doing, as I've said publicly many times, and I don't think the president, in the long run, wants to do that, which is why he has committed to this transition.

"I believe the president and our military are on the right track, which is to turn this over to the Afghans as rapidly as possible in a way that meets their needs to have sufficient stability and capacity to survive, and our needs to prosecute counterterrorism efforts. I think you can do a lot of counterterrorism with a smaller footprint and still manage the progress of Afghanistan.

"Can we do it by 2014? Yes, I believe we can, and I think the president is absolutely intent on preventing this from being the mistake that begged the question that I posed in 1971."