Thursday morning’s letter from President Trump to Kim Jong-un, apparently ending their nuclear negotiation bromance, should come as no surprise. But by once again catching American allies off guard and publicly antagonizing North Korea, the administration has further undermined its own leverage.

Over the past year, the president has repeatedly underestimated the importance of making real trade-offs in diplomacy. These choices appear to be anathema to his “go big or go home” style of deal-making. The Trump administration has been eager to jettison the “weak,” “terrible” deals negotiated by previous presidents — including the Trans-Pacific Partnership, the Paris climate agreement, and the Joint Comprehensive Plan of Action with Iran. With North Korea, he was seeking something bigger and better, “a very special moment for World Peace.”

Instead, the United States may now walk away with nothing.

While it’s true that deals like the Iran nuclear agreement had inherent shortcomings, they also effectively advanced America’s national security. In fact, their limitations reflect a hard-nosed assessment of the risk of the alternatives, the broader geostrategic interests in play and the constraints on America’s leverage. In diplomacy, every deal is an imperfect deal. The question is, how imperfect? And at what cost? Unless you can produce a better alternative, tossing out a less-than-perfect agreement that does advance some concrete goals is an exercise in peril. “Repeal” is almost always simpler than “replace.”

There may still be time to avoid the all-or-nothing trap with North Korea. While it will not be easy to overcome the fallout of provoking a thin-skinned dictator, the United States might now have a chance to focus on a more credible strategy: a deal that constrains, even if it does not immediately eliminate, North Korea’s nuclear and missile programs without offering unacceptable concessions in return. Whether such a deal is possible depends on Mr. Trump’s ability to embrace the art of the imperfect deal.