Rumsfeld had claimed McCain had a "hair-trigger temper" and "a propensity to shift his positions to appeal to the media."

"I respect Secretary Rumsfeld," McCain began by telling ABC's George Stephanopoulos.

"He and I had a very, very strong difference of opinion about the strategy that he was employing in Iraq, which I predicted was doomed to failure," he continued.

"Thank God he was relieved of his duties and we put the surge in. Otherwise, we would have had a disastrous defeat in Iraq," McCain said.

It's not the first time McCain has taken his criticisms of Rumsfeld public.

"We are paying a very heavy price for the mismanagement -- that's the kindest word I can give you -- of Donald Rumsfeld, of this war," he said while running for president in 2007. "I think that Donald Rumsfeld will go down in history as one of the worst secretaries of Defense in history."