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Lindsey Graham to Trump: "Stop being a jackass"

Presidential candidate and South Carolina Sen. Lindsey Graham has "had it" with Donald Trump.

After Trump undermined the military service of Graham's longtime colleague Sen. John McCain, Graham had a clear message for his GOP rival.

"I don't care if he drops out. Stay in the race, just stop being a jackass," Graham said Tuesday on "CBS This Morning."

Graham, who recently retired from the Air Force reserve, said the attention surrounding Trump is "turning into a circus."

"I'm looking for him to be a responsible member of the 16-person primary and stop saying stuff like this," Graham said. "The world is falling apart. We're becoming Greece. The Ayatollah's on the verge of having a nuclear weapon, and you're slandering anybody and everybody to stay in the news. You know, run for president, but don't be the world's biggest jackass."

The controversy over Trump's comments started Saturday at the Iowa Family Leadership Summit when the billionaire said McCain, who was a prisoner of war in Vietnam for five and a half years, was "a war hero because he was captured." Trump was responding to McCain's comments last week when the Arizona senator said the real estate mogul "fired up the crazies" at a rally in Phoenix earlier in the month. Since then, the two have been exchanging insults through the media.

In a phone interview Monday with CBS News' Charlie Rose, Trump blamed the media for misinterpreting his comments.

"The problem is that the media takes it, Charlie, and they'll take a half sentence, they'll take one sentence instead of three sentences, and if you look at it that way it's different, but nothing was said wrong and that's the way we are and it became a story," Trump said.

Still, Graham didn't take Trump's equivocating over his remarks as enough of an explanation.

"John's my friend. He's not a perfect person. He was tortured for five and a half years. When you ask Trump, 'Do you know what he went through in jail?' 'No, it doesn't matter.' Yeah, it does matter. It really does matter," Graham said.

While Trump is leading in polls among Republican candidates, Graham said Trump has now crossed a line with Americans that will not be tolerated.

"This is the beginning of the end of Donald Trump," Graham said.

On Tuesday, the Des Moines Register called for Trump to "pull the plug" on his presidential campaign, saying, "If he were merely a self-absorbed, B-list celebrity, his unchecked ego could be tolerated as a source of mild amusement. But he now wants to become president."

"It ends when the American people say, 'enough,'" Graham said.

Graham, who was with McCain at a New York town hall discussing the Iran nuclear deal, said the Trump sideshow is distracting from more pressing issues.

"The president went to the U.N. instead of his own Congress. That's a sign of weakness, disrespect and a bad deal. [Qasem] Soleimani, the head of the Quds Force that killed 500 Americans at least with copper-tipped IEDs has been taken off the sanctions list, and we can't talk about that because of Donald Trump," Graham said. "To the American people: This is a bad deal. It's going to lead to a nuclear arms race. Let's please move on to things that matter."

Graham went on to slam President Obama over the nuclear deal with Iran, which Congress has until Sept. 18 to review.

"He's the Neville Chamberlain of our time who believes that over the next 15 years, Iran is going to change their behavior, because this deal doesn't require them to do a damn thing in terms of changing their behavior," Graham said. "At the passage, at the end of 15 years, all inspections are lifted. Here's his bet. I don't think he's a bad man, I think he misunderstands the world and the Mideast."

Graham said he thinks there will be enough votes in Congress to override the presidential veto that President Obama threatened in his announcement.

"A 'no' vote ensures that the next president, whoever he or she may be, will have leverage. If Congressional sanctions are left in place, then the next president can get a better deal. We can get a better deal, we must get a better deal. A 'yes' vote takes the Congressional sanctions off the table. The next president has no leverage, and it's very bad for us and Israel," Graham said.