During a Senate hearing this morning on how to combat ISIS, Sen. John McCain (R-AZ) pressed Secretary of Defense Chuck Hagel and Chairman of the Joint Chiefs of Staff​ Gen. Martin Dempsey on how the U.S. would respond if Syrian President Bashar al-Assad's air forces attacked U.S.-backed moderate Syrian forces.

Hagel and Dempsey answered that it is premature to consider that, with the latter suggesting we "defer that challenge into the future."

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“I guess I’m not going to get an answer," McCain said after Hagel kept pointing back to an "ISIL-first" strategy. "But it seems to me that you have to neutralize Bashar al-Assad​’s air assets, if you are going to protect these people that we are arming and training and sending in to fight. Is that inaccurate, General Dempsey?”

McCain further accused Dempsey, the country's top military officer, of not understanding the motivation of the Free Syrian Army to fight against the Assad regime.

“You don’t think that the Free Syrian Army is going to fight against Bashar al-Assad​, who has been decimating them? You think that these people you’re training will only go back to fight against ISIL? Do you really believe that, General?” McCain pressed.

“That’s a fundamental misunderstanding of the entire concept and motivation of the Free Syrian Army. It is Bashar al-Assad​ that has killed many more of them than ISIL has,” McCain said, adding that it will be very difficult to find any Syrian recruits who are interested in fighting only the terror group.

Watch the clip above.

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