Lindsey Graham and Donald Trump (copy)

President Donald Trump greets Sen. Lindsey Graham, R-S.C. (front left), and Sen. Chuck Grassley, R-Iowa, as they meet in the Roosevelt Room in the White House on Jan. 4 in Washington. File/Andrew Harnik/AP

Andrew Harnik

The morning after President Donald Trump tapped John Bolton to become his next national security adviser, U.S. Sen. Lindsey Graham could hardly contain his excitement in an appearance on the president's favorite cable news show.

"The era of leading from behind is over," Graham crowed on "Fox and Friends," citing the former United Nations ambassador's aggressive track record towards North Korea, Russia and Iran.

"John Bolton is a leading from the front kind of guy," Graham said.

The effusive praise marked another notch in the stark departure the South Carolina Republican has taken over the past two years from the blistering criticism he leveled at Trump during the campaign. Deriding Trump back then as an isolationist, Graham once ripped the candidate's "nonsensical" speeches and described him as wholly unfit for the presidency.

"I think it's fair to say I threw everything but the kitchen sink at him," Graham told The Post and Courier earlier this month. 

Yet one of the biggest winners of Trump's recent staffing shakeups has been Graham, who now has the type of hawkish foreign policy team at the White House that’s likely to promote his more interventionist worldview.

With Trump's choice of Bolton, and the ascension of CIA Director Mike Pompeo to become his new secretary of state nominee, Trump's international advisers may now not be too far off from the kind of combative staff Graham would have assembled had his own presidential campaign gotten off the ground.

And Graham knows it.

Pompeo is "going to be a rock star" as the nation's top diplomat, Graham said. Trump "could not pick a better secretary of defense" than former Marine Gen. Jim Mattis. And "nobody is more suspicious of North Korea" than Bolton.

"So he’s surrounded himself with really highly qualified national security advisers, he’s a big fan of the military, and he’s given them the resources and the flexibility they need to keep us safe," said Graham, who sits on the Senate's Armed Services Committee.

Given Trump's infamous propensity to shoot from the hip and change positions by the day, experts warn that Graham should not be taking any victory laps yet. Just because Bolton will have a seat at the table does not mean Trump will heed his advice.

"Bolton may believe that he will be a decider, but Donald Trump has shown that he's willing to ignore his advisers consistently and increasingly," said Jon Wolfsthal, who helped lead nuclear nonproliferation efforts on President Barack Obama's National Security Council. "So I don't think anybody knows what they're getting yet."

Trump proved that true again last week as he continued to demand the military pullout of Syria within months despite strenuous objections of his top aides.

Graham insists that, thought it may not often appear like it, Trump does at least take suggestions under consideration and solicits a wide range of viewpoints.

"The thing about President Trump is he asks a lot of really good questions. He’s curious," Graham said. "President Bush, I liked him a ton personally, he got the big picture on good and evil ... but when it came to Iraq, I don’t think he asked enough questions."

Even when Trump's volatile tweets and off-the-cuff remarks suggest he's ignoring the military advice he's getting, the actions he ultimately takes tend to follow it.

"As a candidate, he can run around like a wild drunk saying crazy things and there’s no accountability," Graham said. "The best way to get sobered up about how the world works is to be the president."

Critics contend Trump still often sounds like a wild drunk (although, on a literal level, he has abstained from alcohol all his life). But when it comes to instituting policy, he often backs off from his more outlandish proposals.

“You can look at the president’s rhetoric, you can look at his bluster, you can look at his tweets," said Scott Buchanan, a political science professor at The Citadel. "But if you actually look at the substance of who’s actually serving in his administration, down the line, it's almost Reaganesque in terms of his Cabinet and appointees.”

Graham's 180-degree transformation from Trump critic to Trump flatterer has paid off in terms of influence. He's earned a consistent spot in the president's ear on international affairs — often in late-night phone calls and occasionally in lengthier White House meetings.

In one of their most recent chats, Graham said he cautioned the president against pulling out of Syria, even if retrenchment may be politically popular. Graham said he ignores public opinion polls on military issues and urges the president to do the same, saying he would "gladly lose an election" if it meant keeping the country safer.

“My time will come and go. The country can operate without me. But I'll tell you what we can’t do is continue to make mistakes that will allow the enemy to have more power," Graham said. 

"But I’m going to make a prediction that the people of South Carolina view radical Islam pretty much the way I do," he added. "They’d rather fight them over there than fight them over here.”

Follow Jamie Lovegrove on Twitter @jslovegrove.

Jamie Lovegrove is a political reporter covering the South Carolina statehouse and congressional delegation. He previously covered Texas politics in Washington for The Dallas Morning News and in Austin for the Texas Tribune.