Washington (CNN) Sen. Rand Paul, R-Kentucky, said Tuesday the U.S. military strike that hit a hospital in Afghanistan raises questions over the U.S.'s continued involvement in that country, 14 years after the U.S. first deployed troops there.

Paul argued the U.S. should no longer be fighting the war in Afghanistan and that "the Afghans need to step it up and defend themselves."

"I think this goes to a bigger question and this is the question President Obama should have to answer: Why are we still at war in Afghanistan? What is the U.S. objective, what's the U.S. mission and why are we bombing anybody in Afghanistan?" Paul, a GOP presidential candidate, told CNN's Wolf Blitzer.

Paul argued that while the U.S. "had a clear cut mission" in Afghanistan following the attacks of September 11, 2001, "that's been long gone for many years now."

Paul, whose non-interventionist foreign policy views are largely out of step with his party's hawkish majority, said the U.S. should avoid a "perpetual war" in Afghanistan and said Afghans "should be able to defend themselves" as the U.S. has poured billions of dollars in aid into Afghanistan.

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