Around the world, the novel coronavirus is mercilessly exposing bad policies and bad institutions. Events of recent weeks have also laid bare the limitations of U.S. President Donald Trump’s trademark personal diplomacy, with events in North Korea the latest example. Although it is unclear what exactly is happening with the health of Kim Jong Un, it is all too clear that Trump’s direct outreach to him has failed.

In this and other cases, Trump has taken to an extreme the long American tradition of hoping that close personal relationships between leaders can cut through the complexities of fraught diplomatic relationships between countries. Yet that approach has proved disappointing if not counterproductive on many fronts at once. Personal diplomacy can, in the right circumstances, be a force multiplier. It is, in the wrong circumstances, an exercise in delusion.

Trump is hardly the first president to put his faith in leader-to-leader relations and the power of his own personality.