Washington (CNN)-Outgoing Secretary of Defense Robert Gates reasserted his belief Sunday that "only time and history" can answer the question of whether the wars in Iraq and Afghanistan were the right decision.
"If the United States is directly threatened, I'll be the first in line to say we should use military force," he told CNN's "State of the Union." "It's wars of choice that I've become more cautious about."
Gates drew a line between the conflicts in Iraq and Afghanistan, describing the Afghan war as a conflict where the United States "had no choice."
"We were attacked out of Afghanistan," he said. But for Gates, Iraq is different.
"What I've said is that the war in Iraq will always be clouded by how it began, which was a wrong premise," he continued. "There were, in fact, no weapons of mass destruction."
Gates also discussed the consequences of losing.
"Failure is a huge challenge for the United States," he said. "And failure will have costs of its own that will linger with us for a long time, as was the case in Vietnam."
For the secretary, who will resign at the end of June, the right thing to do is to end both wars "as quickly as possible."
"My objective in both of these wars has been to end them on terms that enhance United States security, that uphold America's prestige in the world, and our reputation, and advance our interest," he stated.
And Libya is a separate matter altogether.
Describing President Barack Obama's strategy as "disciplined," Gates said he supports the president's actions.
"He made clear there would not be U.S. ground troops in Libya, and he's stuck to that," he said.
"He set a way in which the United States would participate at the beginning."
While Gates would not classify Libya as a "direct threat," he did say it was a "vital interest" for the United States and defended the strategy there, saying, "It seems to me the kind of limited measured role that the president decided on in support of our allies who did consider it a vital interest is a legitimate way to look at this problem."
"(Libyan leader Moammar) Gadhafi will eventually fall," he predicted.
"The allies will be able to sustain this until that happens, and we will support them."
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