In an interview with The Daily Beast on Tuesday, Sen. Rand Paul discussed the war against ISIS—and in doing so, repeated a thoroughly debunked rumor about John McCain palling around with the Islamic extremist group. Needless to say, a certain famously hot-tempered five-term senator and former presidential candidate was not at all amused.

“Here’s the problem,” Paul told The Daily Beast. “He [McCain] did meet with ISIS, and had his picture taken, and didn’t know it was happening at the time. That really shows you the quandary of determining who are the moderates and who aren’t. If you don’t speak Arabic, and you don’t understand that some people will lie to you—I really think that we don’t have a good handle on who are the moderates and who aren’t, and I think the objective evidence is that the ones doing most of the fighting and most of the battles among the rebels in Syria are the radical Islamists.”

Here’s the other problem: The rumor that McCain met with ISIS in northern Syria in May 2013 has been proven false. As reported by The New York Times, pictures of McCain meeting with members of the Free Syrian Army—who have historically opposed ISIS—have been seized upon by conspiracy theorists and McCain skeptics, some of whom have gone as far as to photoshop McCain pinning a medal on the chest of ISIS leader Abu Bakr al-Baghdadi. Emboldening believers is the fact that McCain sometimes misspeaks, like on Monday evening on Fox News, when he asked "Has Rand Paul ever been to Syria? Has he ever met with ISIS?"

In an effort to stake out a position that is at once in stark contrast to that of President Barack Obama and former Secretary of State Hillary Clinton, Paul seems to have found himself outlining a foreign policy that often eats its own tail. Paul opposes arming Syrian rebels, but his post-airstrike plan includes providing “technical support” to other local moderates from countries he has blamed for inadvertently arming ISIS. That said, Paul is uncertain that moderates have the capacity to effectively fight at all, calling that concept “mythical”; he says he does not support Assad, but believes any effort to undermine him is fundamentally misguided, and is what paved the way for ISIS, despite a lack of evidence to support the claim. In short: It’s all a little confusing; and the assertion that McCain was pictured with jihadists is just the beginning.

On Wednesday, according to a senior aide, Paul will appear on the Senate floor for an “extended speech” about “the folly” of arming Syrian rebels. But first, there's a tussle with the senior senator from Arizona to take care of.

Asked by The Daily Beast about Paul using the palling-around-with-terrorists rumor to attack him, McCain huffed: “I can’t believe Rand is still repeating this stuff, which came from a Hezbollah newspaper in Lebanon! He’s getting his information from Hezbollah. It’s outrageous…I don’t know if Rand is dishonest or misinformed…I met with the Northern Storm and Gen. Idriss, who was the head of the Free Syrian Army. Most of the guys in that picture are dead now, killed by ISIS. It’s just ridiculous.”

It wasn’t just a Hezbollah newspaper in Lebanon. The lie was also printed by the liberal blog Wonkette, and a version of the lie—this one claiming the Free Syrian Army is working with ISIS—appeared on the conspiracy theory-friendly rag Infowars.com.

Mouaz Moustafa—executive director of the Syrian Emergency Task Force, which represents the moderate opposition in Washington—reiterated McCain’s point: “I’m incredibly surprised that a United States sitting senator is spreading a rumor that is completely baseless. It is very ironic that the biggest enemies of ISIS are being called ISIS by people who simply do not know the facts. When it comes from a United States senator, it is quite disturbing.”

Paul and McCain do not exactly have a history of slumber parties and hair-braiding. In 2013, after Paul’s 13-hour filibuster over U.S. drone policy ahead of the confirmation of CIA Director John Brennan, McCain called him a “wacko bird” (McCain later apologized). Not long after, Paul first criticized McCain for having his “picture taken with some kidnappers.” This summer, McCain charged that Paul is “part of a wing of the party that has been there prior to World War I, that is a withdrawal to ‘Fortress America.’”

At least some of the bad blood arose from Paul's willingness to stake out positions on matters of national security that were passive in comparison to most of his colleagues in Washington—especially hawks like McCain. About a month ago, however, Paul began showing a different side. He announced that he would support reengaging in Iraq to defeat ISIS with airstrikes. Just last week, in news first reported by The Daily Beast, Paul said he would support furthering the war against ISIS to include airstrikes in Syria, but would oppose arming moderate rebels.

On Tuesday, Paul further explained his position, claiming that it was the arming of Syrian rebels that allowed for the rise of ISIS, because the weapons have made their way into extremist hands: “These weapons are being used against Americans. They weren’t, I think, purposely given to ISIS—but they were given to very weak players, and ISIS took them from those players.”

Paul noted the obvious counter-argument to his statement: reports indicate that the number of weapons provided to rebels was insignificant: “Some would say, ‘Oh, we hardly gave any weapons,’” but even if ISIS failed to obtain any U.S.-weapons, Paul explained, enough were supplied by “various places” like “Saudi Arabia, Qatar, Kuwait, Turkey, [and] Libya” to “[keep] Assad at bay [and provide] a safe haven for ISIS. I think, without question, ISIS has grown stronger because of our support of the Syrian rebels.”

But Paul also told The Daily Beast that after the bombing campaign ends, he believes that “components of Islam” should fight on the ground, and that the U.S. should support them: “I don’t mind helping them through technical support, through sophisticated intelligence, drones, Air Force, etc. But the people on the ground fighting these battles, going hand-to-hand with ISIS, need to be their fellow Arabs and those who, I think, and hopefully do, represent civilized Islam.” Paul said he believes Iraqis, Saudis, Kuwaitis, Qataris, Turks, and Kurds should be engaged in the on-the-ground fight. Note: These countries are the same ones Paul blamed in the previous breath for helping to arm ISIS.

Later, Paul seemingly negated his post-airstrike plan when he expressed skepticism at the idea that moderate rebels could actually band together to fight effectively, calling the idea “mythical”: “The mythology is that they are going to be some great fighting force. It's not that they don’t exist—the mythology is that they’re a great fighting force that’s sort of waiting there in the wings. The bottom line is, even if they were strong fighters, if you were beating back Assad, you’re still providing a space for ISIS. Anything we’ve done to degrade or keep [Assad] away from these territories has been to the betterment of ISIS.” This does not take into account the fact that Assad has a history of making strange alliances—like with al Qaeda.

Asked how, as a vocal opponent of Christian persecution, he could support Assad, who has slaughtered hundreds of thousands of his own citizens—including Christians—Paul said: “There’s not anything good that you can say about Assad. He’s a horrible autocrat, he’s a dictator, he’s had human rights violations, he’s gassed his own people, there’s nothing good to say, but it is a complicated and murky civil war.” But, Paul claimed, “The vast majority of Christians are living in areas that are protected by Assad, they have aligned themselves with Assad, and if you ask them, ‘Who do you want to be in charge of your country: Assad or ISIS?’ I think, hands down, they’d pick Assad.”

Paul said that although there's nothing positive about Assad, “I’m just saying, if we have a choice of secular dictatorship versus chaos, then maybe we shouldn’t be involved, and maybe we shouldn’t be so assertive that we think we know what’s best.”

Paul’s skepticism regarding intervention is what endeared him to many of his supporters in the first place. Asked, then, how he is certain the threat ISIS poses isn’t being overstated, he said: “I think that emotions do run high, and I admit, frankly, that I’m like anyone else, susceptible to a certain degree, to the emotions of seeing Americans beheaded. So, I think that is a component of it.” (Paul said he has not watched the videos of the beheadings.) “I think also that there is a real threat, possibly a real threat to the consulate as well as to the embassy and, I think, left to their own devices, probably to the mainland. But you’re right, Homeland Security and others in our intelligence community have said currently they’re not—and I think the president was careful to say this in his remarks—that currently they are not a direct threat to the homeland. I don’t think anybody believes that tomorrow there’s going to be an attack.”

Without prompting, Paul brought up former Secretary of State Hillary Clinton, who is widely expected to mount a campaign for the Democratic nomination. “I spent about a year criticizing Hillary Clinton for not providing adequate security for Benghazi,” he recalled. “I think it’s consistent with that argument to say, ‘Yes, we have a consulate in Arbil that’s probably within striking distance, and maybe even within military capabilities of ISIS.’”

Later, Paul again criticized Clinton without prompting: “This will be difficult for Hillary Clinton if she’s the nominee, because she has been such an advocate of intervention, and so hawkish on all of these things, whether it’s Syria or Libya—and Libya is, without question, an utter disaster. It’s going to be very hard for her to explain, one, a lack of defense to the Benghazi consulate, the death of the ambassador, [after] six months’ worth of request for security, but even more difficult will be to explain, is America safer because of the Libyan war? Even more difficult to explain [will be] why they did this without congressional authority, why they disobeyed the Constitutional mandate to ask Congress.”

But Hillary clearly isn’t the only political opponent in Paul’s sights. In addition to his Wednesday speech on the Senate floor, Paul will also be going after “a colleague, possibly the one from AZ.” Wonder who that could be?

— with additional reporting by Josh Rogin