John McCain’s slip of the tongue won’t help him quell Internet accusations that he once met and took pictures with members of the terrorist group the Islamic State in Iraq and Syria (ISIS).

Appearing on Fox News’ “Hannity” Monday night, the Arizona Republican senator went off on Rand Paul after host Sean Hannity brought up the Kentucky Republican senator’s concern that providing weapons to Syrian rebels will only end up benefiting ISIS.

“Has Rand Paul ever been to Syria? Has he ever met with ISIS?” McCain fumed, certainly meaning to say the Free Syrian Army instead of ISIS.

McCain has long advocated giving weapons to what he considers the moderate opposition trying to overthrow the dictatorial regime of Bashar al-Assad. Critics of such a policy, including Paul, warn that there are no true moderates of any strength fighting Syria’s brutal strongman. (RELATED: Expert Who Traveled With Syrian Rebels Says So-Called “Moderates” Are Muslim Brotherhood-Style Islamists)

Back in March 2013, McCain actually snuck into Syria to meet with some of the Syrian rebel opposition. Since that trip, McCain’s political enemies have accused the 2008 Republican presidential nominee of not only meeting and taking pictures with the so-called moderate opposition, but also members of ISIS. McCain says he did nothing of the sort and no real evidence has ever been provided to show that any of the men McCain took pictures with were ever affiliated with ISIS.

But his slip up Monday night on “Hannity” won’t help him put those Internet accusations to rest.

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