SEOUL – National Security Advisor John Bolton, talking his usual tough talk, may have prompted North Korea to walk away from the much-ballyhooed June summit between Donald J. Trump and Kim Jong Un. Certainly it led to a clarification: there is no way in hell Kim is going to give up his entire nuclear arsenal and allow inspectors to crawl all over his country before North Korea sees “the benefits start to flow,” as Bolton proclaimed on ABC over the weekend.

In a statement carried by the North Korean news agency, obviously with Kim Jong Un’s approval, the first vice-minister of foreign affairs, Kim Kye Gwan feigned something close to heartbreak on hearing such “unbridled remarks” being “recklessly made” in the United States, and singled out Bolton in particular: “We do not hide our feeling of repugnance toward him.”

Pyongyang left open the possibility the summit could still take place. There was no attack on the thin-skinned American president, but if he thinks his administration can continue to brag about squeezing North Korea before he sits down to talk to Kim, he’d better think again.

Trump has said many times he might walk out of the talks scheduled for Singapore next month if he finds they are not going well – by which he says he means no more nukes. Now Kim looks like he might beat him to the punch.

Call it a bargaining position or a non-negotiable hard line, but North Korea is determined not to give up the nuclear program initiated by leader Kim Jong Un’s grandfather, Kim Il Sung, which achieved its initial successes under Kim’s father, Kim Jong-Il, and then was enshrined in the constitution and elevated to its highest technical level last September with the North’s sixth nuclear test – this one believed to be a hydrogen bomb capable of wiping out entire cities.

Kim had agreed “complete denuclearization” of the entire peninsula was to be desired, but that did not mean he agreed to do anything right away – or ever.

American wishful thinkers should have figured all that out well before North Korea’s powerful vice foreign minister Kim Kye Gwan said Wednesday "we will not be interested in talks anymore if [they] only try to push us unilaterally into a corner and force us to give up nukes.” Moreover, he added, in comments carried by the North’s state media, "It would be inevitable to reconsider whether to respond to the upcoming summit with the U.S."

Just what was it that drove the North Koreans into this position after all the happy talk from Trump, who has suddenly found Kim “honorable” and “trustworthy” after reviling him last year as a “little rocket man” who was on “a suicide mission” if he persisted in threatening the U.S. with nuclear-tipped missiles?

One factor might have been “Max Thunder,” the joint U.S.-South Korean air exercises opened last Friday in which U.S. and South Korean war planes are spending two weeks testing their “inter-operational capability” – a show of force that North Korea routinely, annually lambasts as revealing plans to invade the North.

North Korea gave that as the reason for cancelling talks Wednesday in which senior officials from both North and South were to have met at the same truce village of Panmunjom where Kim and South Korean President Moon Jae-in staged their summit on April 27. The North Koreans, though, knew full well the exercises would be held as scheduled, and Kim had not been expected to raise severe objections to them, just as he managed to tolerate war games last month involving U.S. and South Koreans, mostly on the ground, many played on computers.

Kim Kye Gwan, a familiar figure in negotiations with the Americans that led to unfulfilled agreements more than 10 years ago, did not even mention Max Thunder. The real reason for his statement goes back to some of the tough talk coming from Washington about how determined the Americans are to bring about an end of North Korea’s nuclear program. And the toughest talk was from Bolton on ABCs “This Week” last Sunday.

As Bolton told ABC’s Martha Raddatz,“We want to see the denuclearization process so completely underway that it’s irreversible.” Getting specific, he said that North Korea’s nuclear warheads, under inspection, should be shipped to Oak Ridge, Tennessee, where they would be systematically destroyed at the nuclear research center run by the Department of Energy.

The gut response to that comment has nothing to do with Bolton’s hawkish or conservative reputation. Rather, the question is: “What was he thinking?” or “Who was he kidding?” or “Was he out of his mind?” Does any sane person think Kim is going to open the doors to the Yongbyon nuclear complex, 60 miles north of Pyongyang, where his engineers and technicians have fabricated about 40 to 60 warheads by now?

And Bolton did not stop there. The North Koreans, he said, would have to reveal all the places they’re working on nuclear weapons and ballistic missiles to make sure they’re living up to their agreement. That comment, aside from raising questions about Bolton’s basic judgment, calls into question his knowledge or understanding of North Korea. The image of a bunch of nosy foreigners poking around hundreds of caves and redoubts and tunnels where the North Koreans may be stashing that stuff is fantasy. It’s not going to happen. Not as long as Kim is in charge.

The dreams of a deal whereby Kim sees the light, acquiesces and bows down in talks with Trump may have been encouraged by one gesture the North Koreans are making. That’s the closure and destruction of the nuclear test site at Punggye-ri, in a mountainous region far northeast of Pyongyang, to be carried out between May 23 and May 25. That’s going to be a tremendous event, live on TV, but it’s all for show.

The site, where North Korea has conducted all six of its nuclear tests, is presumed no longer usable. The sixth test, last September, was so powerful it appears to have collapsed part of the mountain in which the test tunnel was dug. Tremors were felt over the entire region. By inviting a select group of foreign journalists to see and hear the destruction of the site, Kim is able to distract attention from the Yongbyon facility about which he has said not a word.

It would be easy to say all signs point to a subterfuge while Kim preserves the North’s status as a “nuclear weapons state” but Kim Kye Gwan’s statement strips away the view that Kim may be trying to fool the Americans into thinking he’s ready to go along with their idea of denuclearization. Nor, certainly, is there any chance that Trump when or if he sees Kim can talk him into shutting down and shipping out his nuclear facilities, warheads and all.

The Trump-Kim summit may be pointless if the Americans still think they can go home with an agreement of the sort envisioned by Bolton, but the South Koreans have other reasons to keep talking.

No sooner had Kim Kye Gwan’s statement gotten out than Secretary of State Mike Pompeo was on the phone with the South’s f oreign minister, Kang Kyung-wha. Kang left no doubt, according to the foreign ministry, that the South would do all it could to get North-South talks on track again, keeping up the “momentum” from April’s Moon-Kim summit.

North and South Korea have much to talk about, including opening of basic rail and road traffic, commercial ties and reunions between families divided by the Korean War. The current war games will end in another 10 days, but day-to-day issues remain.

If compromise on denuclearization is not going to happen, at least there may still be hope for easing North-South tensions. Time is going by. The old folks are dying off. There hasn’t been an opportunity for North-South family reunions for three years.