Jonathan Ernst / Reuters

Senator Lindsey Graham is irrepressibly cheerful, but he’s not very happy about the world these days.

“I think I understand exactly the mess we’re in,” the 2016 Republican presidential hopeful said on Monday. “Leaving Iraq too soon is just as bad as not having enough [troops] when you went in. At the end of the day, Syria is hell on earth. And there’s no way to fix Iraq unless you fix Syria, and you’re not going to fix Syria until you deal with [Syrian President Bashar al-] Assad, ‘cause no Arab army is going to just fight ISIL.”

“I spent a lot of time learning this crap,” Graham concluded, “and I am ready to go.”

“And Putin? Your worst days are ahead, pal.”

The senator from South Carolina spoke with The Atlantic’s Jeffrey Goldberg on Monday at the Aspen Ideas Festival. Graham presented a stark view of a world full of challenges that only the threat or use of military force might resolve. And he delivered that dour view with wit, quips, and a mischievous grin that frequently provoked the crowd into open laughter, even as it absorbed his litany of woe.

Graham was unequivocal about the Iranian regime and the U.S.-led negotiations over its nuclear program. “I think these guys are religious Nazis with an end-of-days view of their religion and that they’re dangerous as hell,” he said. He attacked the Obama administration for “sitting down and talking to people who’re nuts as if they’re not nuts.” An Iranian nuclear weapon, he said, would be shared with a terrorist organization “at a minimum,” and might be used by Iran itself. “Do they want to kill a lot of us?” he asked. “I think they do.”

Negotiations, he insisted, had proceeded from a set of mistaken premises. “There are no moderates in the Iranian government,” he said. “There are people who present well in the Iranian government who’re going to do as the ayatollahs tell them.” Instead of seeking compromise, he suggested setting out a straightforward ultimatum: accept a peaceful nuclear program with anytime, anywhere inspections, or face the use of military force. “A bad deal would deny us anytime, anywhere inspections, given the fact they lie and cheat,” he said.

“The problem we’ve got is that [the Iranians] don’t think we’ll use military force to stop their nuclear ambitions,” Graham argued. “It will be the policy of the Graham administration that if we can’t negotiate a good deal to end your nuclear ambitions, we’ll use military force to stop you from achieving your nuclear ambitions. And when I say military force … I mean going after your infrastructure not only nuclearly, but your ability to wage war.”

Graham set Iran within a broader context of conflict in the Middle East. There were, he said, two key developments in the region. “There is a fight between a radical strain of Shia and Sunni religion and most people, and if we don’t take sides we’re making a mistake,” he said. And, he added, “there is a second thing going on: Young people are not going to live in dictatorships for our convenience anymore.” Instead of withdrawing from the Middle East, he promised, “if I’m president of the United States we’re going to help these people. We’re going back and we’re not leaving till we get it right.”

And that, he explained, meant sending ground forces back to the Middle East, to destroy the Islamic State. “I don’t know how to defend us over here without some of our soldiers going back because the armies over there are failing miserably,” he said. “I think there is a tie between the rise of ISIL in Syria and Iraq to homeland-security threats here. I think it is essential that America stop the slaughter, that when you crucify children, when you decimate an entire religion and America does nothing about it, we always live to regret it. This is the 1930s all over again, and this ISIL threat is something that will come our way soon if we don’t stop it over there.”

Graham, who retired from the Air National Guard after 33 years of service last week, laid out a set of specific proposals: deploying 10,000 ground troops, multiple aviation battalions equipped with attack helicopters, forward air controllers, and battalion-level advisors embedded with local forces. That force, he explained, would not only fight ISIS in Iraq, but also serve as the nucleus for a coalition, built with forces from Turkey and the Arab states, that could advance into Syria and dislodge ISIS.

“This is a religious war,” he warned. “They would kill everybody in this room regardless of your ideology because you do not bend to their faith. There is no substitute for winning this conflict. There is no substitute for America.”

“Please don’t leave Aspen thinking that a Lindsey Graham presidency would be easy,” he told the crowd, “but it would be successful.”

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