President Donald Trump's aides and associates cast Thursday’s cancellation as a decisive move that showed the president’s sharp negotiating instincts can translate to the world stage | Jung Yeon-Je/AFP via Getty Images Inside Trump’s North Korea gamble The US pullout from the planned June 12 summit was announced not by tweet, but in a formal letter after the president consulted with top national security aides.

Past American presidents have approached nuclear talks with North Korea as a matter of delicate statecraft, requiring seasoned experts and long technical briefings.

For President Donald Trump, it was just another exercise in what one Trump friend approvingly called “the art of the deal.”

Trump aides and associates cast Thursday’s cancellation of a planned June 12 summit with North Korean leader Kim Jong Un as a decisive move that showed the president’s sharp negotiating instincts can translate to the world stage.

“He is not taking the guy’s shit,” boasted the Trump friend, who speaks with the president frequently.

But critics said the reversal simply proves that Trump is out of his depth when it comes to high-stakes diplomacy. At the same time, some were relieved that Trump will no longer head to Singapore planning to “wing it,” as one former U.S. official familiar with Trump administration planning described the White House’s preparations — or lack thereof — for the scrubbed meeting.

The events leading up to the abrupt collapse of the summit signaled that Trump’s recently revamped national security team, particularly national security adviser John Bolton, is succeeding in imposing some traditional order on the impetuous president.

In contrast to Trump’s impromptu March decision to accept the meeting, which surprised and alarmed his closest advisers, his decision to scuttle the summit came after consultation by phone on Thursday morning with Bolton, Secretary of State Mike Pompeo and Secretary of Defense Jim Mattis.

The cancellation announcement came not via Twitter but in a formal letter dictated by the president himself and released by the White House press office. The document cites North Korea’s “open hostility” in recent days, particularly a statement blasted out Wednesday evening threatening nuclear war.

The statement was the first time in a week that the U.S. had heard from North Korean officials, a senior White House official said.

“A trail of broken promises” on the part of the North Koreans triggered the president’s decision to back off talks, the same official added.

Though it played a small role in the 2016 campaign, North Korea has assumed a dominating role in Trump’s early presidency. After a private warning from former President Barack Obama that North Korea would be “the most urgent” problem Trump would face, Trump’s National Security Council turned its attention to the country early on — making it the first issue to trigger a full interagency review under then National Security Adviser H.R. McMaster. The result of that strategic reassessment was the administration’s “maximum pressure” campaign, a combination of heightened sanctions and bellicose rhetoric.

Before Kim extended an invitation to meet in March, Trump referred to him derisively as “Little Rocket Man” and bragged that his nuclear arsenal is “bigger and more powerful” than his. Trump flashed that confrontational tone again in his Thursday letter to Kim, in which he warned of America’s “massive and powerful” nuclear capabilities.

The president’s allies credit the maximum pressure campaign with bringing Kim to the table, and applaud Trump now for canceling the summit after official statements from Pyongyang also threatened Bolton and Pence and, as one senior White House official noted on Thursday, threatened “nuclear-to-nuclear showdown.”

American officials arrived in Singapore last week for a planned meeting with their North Korean counterparts, but the counterparts never showed up, according to the White House official. “The North Koreans didn’t tell us anything, they simply stood us up.”

Trump allies cast his decision as the latest in a series of gutsy moves by a president determined to keep his campaign promises and not get rolled by foreign adversaries.

“North Korea has a long history of demanding concessions merely to negotiate,” Senator Tom Cotton, R-Ark., one of the president’s closest allies in Congress, said in a statement. “While past administrations of both parties have fallen for this ruse, I commend the president for seeing through Kim Jong Un’s fraud. As I have long said, our maximum-pressure campaign on North Korea must continue.”

Trump’s foreign policy has been guided by his desire to look tough. Earlier this month, Trump delivered on his longtime vows to scrap the Iran nuclear deal, insisting that he could impose stricter terms on Tehran.

“I never get too attached to one deal or one approach,” Trump wrote in his 1987 bestseller, “The Art of the Deal.” “For starters, I keep a lot of balls in the air, because most deals fall out, no matter how promising they seem at first.”

And he pushes back hard on those he feels are treating him unfairly, he wrote. “The risk is you'll make a bad situation worse, and I certainly don’t recommend this approach to everyone. But my experience is that if you’re fighting for something you believe in — even if it means alienating some people along the way — things usually work out for the best in the end.”

Trump puts a premium on psyching out his opponents, and some North Korea experts said they suspect Kim and his advisers might be rattled by the president’s unpredictable behavior.

“Probably in their darkest moments they’re afraid of Trump, ’cause he’s erratic, but you’ll never see it and they’ll never show it,” said Joel Wit, a former State Department official and an expert on North Korea.

Yet Trump’s detractors see a president who stumbled irresponsibly into high-stakes negotiations only to realize, with the event looming — the originally scheduled summit date of June 12 “is 10 minutes from now,” a Trump official said Thursday — that he is unprepared.

Now, these critics say, Trump has needlessly angered the North Koreans — as well as risked his damaging his relationship with South Korea, whose president worked hard to bring Trump and Kim together, and perhaps also China. The result could be that the economic sanctions Trump officials credit with bringing Kim to the table may become harder to maintain.

“The people in Washington are operating on the assumption that they can just go back to maximum pressure and that’s not going work. Once Trump went down this road, the air was let out,” Wit said.

For weeks Trump advisers — particularly Bolton and Pence — have warned that it is folly to assume that Kim will surrender his nuclear arsenal voluntarily. Bolton has told associates that the U.S. has frighteningly little visibility into North Korea. Pence even began referring to himself inside the White House as the “skunk at the garden party.”

Both Pence and Bolton enraged the North Koreans through a series of television appearances in which they publicly cited Libya’s 2003 surrender of its nascent nuclear program as a blueprint for Kim’s regime. North Korea considers the analogy insulting, in part because Libya’s leader, Muammar Gaddafi, was later overthrown and murdered.

Secretary of State Mike Pompeo told Congress on Thursday that North Korea has not responded to American officials working to plan the summit. “Over the past many days, we have endeavored to do what Chairman Kim and I had agreed, which was to put teams, preparation teams together to begin to work to prepare for the summit — and we have received no response to our inquiries from them,” he told the Senate foreign relations committee.

The looming question is to what extent the summit’s cancellation means a reversion to the saber-rattling on the president’s part, which prevailed before meaningful communication between the two countries began.

One Asia expert familiar with the White House deliberations said that, as the president’s bellicose rhetoric escalated last summer and fall, Trump insisted on military first-strike options that most regional analysts and military officials consider extremely dangerous.

While McMaster and the NSC were “trying to control Trump” and manage the risk, they never ruled out the military option. Victor Cha, then Trump’s planned nominee for ambassador to South Korea, warned White House officials that it is reckless to consider a “bloody nose” strike — that no first strike against Kim would result in anything but disaster. He would later write for the Washington Post that some officials believe such an attack is “the answer” to the North Korea problem. Five weeks later, Trump accepted Kim’s invitation to meet.

The Asia expert said it was always unclear how serious Trump might have been about attacking North Korea, or whether the planning — and associated leaks — were an effort to “make the bluff credible.”

While the president has left the door open for a meeting with Kim — “it’s possible that the existing summit could take place or a summit at some later date,” this expert said — former national security officials are more worried about an escalation of tensions.

“With no summit in the offing, the preventive war narrative is likely to make a comeback,” said Van Jackson, a former Obama Pentagon official who specializes in Asian security and defense. “Dangerous times ahead.”

Nahal Toosi contributed reporting.