More specifically, the Kim regime has negotiated away its decades-old Yongbyon nuclear reactor several times, but resisted ceding other elements of its increasingly sophisticated nuclear program. Stopping the production of fissile material and sending international inspectors to Yongbyon could be accomplished today, the Korea expert Joel Wit told me, but going beyond that “gets really tough.”

And while North Korea did commit in writing in 2005 to “abandoning all nuclear weapons and existing nuclear programs,” in return for the United States proclaiming that it had “no intention to attack or invade [North Korea] with nuclear or conventional weapons,” it has also signaled that it will only fully divest itself of nuclear weapons if its circumstances change dramatically—as in, for instance, America withdrawing its troops from the Korean peninsula or ending its military alliance with South Korea, which the U.S. has shown no interest in doing. (The 2005 statement arose out of a years-long process called the Six-Party Talks involving the U.S., North Korea, South Korea, China, Russia, and Japan that broke down at the end of the Bush administration over that perennial sticking point: verification of North Korea’s compliance with the agreement.) When South Korean officials tell us, as they did this week, that their North Korean counterparts say there’s “no reason for them to possess nuclear weapons as long as military threats to the North are eliminated and the regime’s security is guaranteed,” it may be a bit like when U.S. officials say there’d be no reason for America to maintain its nuclear arsenal if all other nuclear powers gave up their weapons.