Maybe the Trump team think this is just the way things are done here on the peninsula. DeHart’s remarks bear an uncanny resemblance to those of the North Korean negotiator who broke off talks in Stockholm last month with U.S. nuclear negotiator Stephen Biegun, claiming the U.S. had added nothing to the dialogue on the North’s nukes and missiles.

It’s not only the U.S. presence in South Korea that’s imperiled, bases also are in doubt in Japan, whose conservative prime minister, Shinzo Abe, is balking at Trump’s demand for a $4 billion increase in the annual Japanese contribution.

Bruce Bennett at RAND raises the question of who has military superiority in the region if the U.S. breaks its historic alliances. North Korea has 1.1 million troops plus 30 to 60 nuclear warheads, he notes, while South Korea’s armed forces, bereft of nukes, will be down to 365,000 by 2022.

“If the North is in a position of dominance,” Bennett asks, “what will the rest of the world conclude about the value of an alliance with the U.S., and what will the world conclude about the need for national nuclear weapon programs?” Such a move could well lead to “the end of effective U.S. nuclear nonproliferation efforts.”