Why would POTUS think the NorKs were preparing to walk, which would have been a colossal embarrassment for the White House? Because they already had, sort of. From WaPo:

U.S. officials had grown concerned that Kim’s deputies had gone silent on preparations for the summit. Secretary of State Mike Pompeo — who traveled twice to North Korea and was regarded inside the Trump administration as the good cop to Bolton’s enforcer — blamed Pyongyang for the breakdown in communication in recent days.

The United States “received no response to our inquiries from them,” Pompeo told a Senate panel Thursday. “We got a lot of dial tones.”

U.S. officials were further frustrated last week when a senior North Korean delegation failed to show up for a planning meeting in Singapore, leaving a team led by Hagin in the island country with little to do.

“They waited, and they waited,” a senior White House official said. “The North Koreans never showed up. The North Koreans didn’t tell us anything. They simply stood us up.”

There were a *lot* of bad vibes coming from the North the past few weeks. They attacked Bolton in a statement; they demanded the cancellation of military exercises between the U.S. and the South; they were no-shows in Singapore, we’ve now learned; and then they attacked Pence in another statement. If Trump had quietly tolerated all of that and then Kim turned around and pulled out of the summit, it would have left the White House looking pitifully weak, more desperate to hold a meeting with a lunatic regime than vice versa. Trump decided to claw back a little prestige by blowing up the meeting before Kim could:

[T]he president, fearing that the North Koreans might beat him to the punch, wanted to be the one to cancel first, multiple officials told NBC News.

“There was no hint of this yesterday,” a person briefed on the summit preparations said, calling Trump’s decision “high risk, high reward.”

Makes sense, although I’m not sure what’s stopping Kim at this point from rescheduling and then getting even with Trump by sending the White House his own letter out of the blue canceling on the new summit. Trump’s still eager to hold the meeting and he doesn’t seem to be demanding any new concessions from the North to make it happen. What he appears to want is an attitude adjustment. So Kim’s going to adjust his attitude … and then, a week or two later, he might just readjust it again to “nah, forget it” to humiliate POTUS.

After all, Trump can’t back out of the summit a second time. If he walks again, it’ll have to be for good; otherwise he, and the process, will look ridiculous. If Kim rejoins negotiations, he suddenly has that bit of extra leverage. And even if he doesn’t, this might work out for him. As one foreign-policy expert said to WaPo of the NorKs, “If the summit with Trump can be salvaged, they get the benefit of being treated as an equal with the superpower and staged process of denuclearization. And if it can’t be, the result is that a wedge has been driven between South Korea and the U.S.”

And maybe not just the U.S. and South Korea. Here’s a cryptic but noteworthy comment Trump made at his press conference yesterday:

Trump: I think I understand why our dialogue with North Korea soured, but I won't tell you right now pic.twitter.com/GN2ZbdJE7g

— Washington Examiner (@dcexaminer) May 24, 2018

He did seem to hint at what he was thinking at the same photo op, though: “When Kim Jong Un had the meeting with President Xi, in China, the second meeting . . . I think there was a little change in attitude from Kim Jong Un.” Presumably he suspects China leaned on Kim to be more obstinate towards the U.S., possibly to gain leverage over America in China’s trade negotiations with the White House. If true, POTUS now has a choice to make. What does he value more, better relations with North Korea or toughness towards China on trade? Because, per Xi, it might be an either/or proposition.

Speaking of not-so-crazy theories, here’s Scarborough breathing a sigh of relief that the summit was canceled and finding strange new respect for John Bolton, whom he blames/credits for having sabotaged it with his public chatter about the “Libya model.” That’s not that far-fetched; read this if you missed it the other day to see why. It’s no secret that Bolton thinks diplomacy with the North is pointless, as he’s said so many times as a TV pundit. It’s also no secret that any mention of Libya in the context of denuclearization was guaranteed to spook the NorKs, as they’re terrified of meeting Qaddafi’s fate if they disarm. If Bolton was looking to undercut the prospects of the summit, he said exactly the right thing to make it happen. (Mike Pence got in on the act later too by citing his own “Libya model” of regime change if Kim didn’t denuke.) In fact, per NBC, Bolton was the driving force in convincing POTUS to pull out yesterday, allegedly much to Mike Pompeo’s annoyance. If the summit is rescheduled, will Bolton try to tank it again?