But the approach, which has included three face-to-face meetings, has resulted in no such breakthrough while arguably disempowering top aides to Trump as well as U.S. diplomats. Some U.S. officials have found it hard to even get in touch with their North Korean counterparts; in some prominent cases, they’ve been publicly scorned. Trump’s game plan also essentially sidelined U.S. allies in Asia, as well as U.S. rival China, all of whom have a great deal at stake in Pyongyang’s future.

Now, amid rumors that Kim is sick or even dead, current and former U.S. officials and North Korea analysts say Trump’s mano-a-mano diplomacy looks shakier than ever because the Trump-Kim relationship has been the only one that truly mattered.

If a new leader emerges in North Korea, he (or she) may decide to grow the country’s nuclear arsenal as a way of consolidating and projecting power. And with U.S.-Chinese relations on a downward spiral due to fallout from the coronavirus pandemic, the idea of international cooperation to diplomatically pressure North Korea and maintain economic sanctions on the country seems remote.