The Trump administration could mimic the Obama administration and patiently ratchet up international sanctions against North Korea as a way of pressuring it to return to negotiations over their nuclear program, Cha said. It could crack down on North Korea’s revenue from exporting slave labor to countries like China and Russia. But neither of those approaches will change one stubborn, significant fact: Roughly 85 percent of North Korea’s external trade is with China. And China has the ability to shut down that trade, ending barter trade along its border with North Korea and preventing North Koreans from using Chinese banks.

China, the world’s largest economy by some measures, “doesn’t need that trade,” Cha continued, and choking off its economic relations with North Korea is “the only thing that we can do at this point. It’s not going to solve the problem [of North Korea’s nuclear program], but if the North Korean leadership doesn’t have the money to buy Mercedes-Benz and cognac and all these other things, and if their bank accounts are being frozen in Chinese banks and elsewhere, they’re not going to be in a good position.”

As for the ultimate goal of placing North Korean leaders in such a bind, the “diplomatic answer is that that would then be a segue to negotiations in which everybody would be united [on] the terms for North Korea to freeze and then dismantle their program,” Cha explained. “The undiplomatic answer is that it puts enough pressure on the regime that there will be some sort of internal problems, and that Kim Jong Un might be challenged by others who see a better path for North Korea.”