Maybe they were never really bolted on in the first place, but in recent weeks it looks very clear that the wheels have come off whatever was agreed to or understood between North Korean leader Kim Jong Un and U.S. President Donald Trump in Singapore. As bilateral negotiation efforts falter and North Korea returns to its pugnacious pronouncements of the evils and deceitfulness of U.S. policy, the question now is where to go from here. Of particular concern is whether “maximum pressure,” as the Trump administration sanctions program was dubbed, can be revived, and whether Washington can muster the diplomacy to ensure that the regional players are on board for what could be a bumpy ride ahead.

When Trump agreed to a summit with his North Korean counterpart, the initiative was widely hailed as a welcome departure from angry threats, a Nobel Peace Prize–worthy effort to solve the North Korean nuclear crisis through dialogue. It was music to the ears of many, especially to South Korea, where talk of war—from a U.S. administration no less—can be particularly alarming.

But in the ensuing implementation and follow-up, Singapore may turn out to have done more harm than good. To date, almost three months after the summit, there is scant evidence that North Korea is prepared to abandon its nuclear programs on an acceptable time frame, certainly not on National Security Adviser John Bolton’s one-year schedule or on Secretary of State Mike Pompeo’s seemingly more generous two-year term. Instead, North Korea has returned to the tired demand that what it needs before moving toward denuclearization is some kind of proof that the United States has abandoned its “hostile policy.” In the past, Pyongyang has been vague on what would constitute sufficient proof of this abandonment. But in Singapore and in the various track two negotiations that have followed it, it seems increasingly to come down to signing a peace treaty or normalization agreement that would eventually lead to the pullout of U.S. troops from South Korea. Although North Korea has not pushed for this to happen immediately, it has pressed for the United States to cease its joint military exercises with South Korea in the meantime.

U.S. forces are in South Korea to help defend that country from another invasion from the North. That they could be there as the vanguard of an invasion force is the stuff of North Korean fantasy, but in the absence of serious North Korean negotiation, Washington has oddly accepted Pyongyang’s proposition that it needs to demonstrate that it has no hostile intent. Trump himself started this exercise in preventive capitulation by pledging that the United States would get to work immediately on a treaty to reassure North Korea that the United States will not attack or invade them. He also threw in the sweetener that Washington would cancel upcoming joint exercises with South Korea (which he referred to, echoing North Korean language, as “war games” that were “very provocative”) and that, looking down the road, it will try to withdraw those very U.S. troops that supposedly make the North Korean leadership sleepless at night. Such ideas have been discussed before, but only in the endgame context of a denuclearized North Korea, or at the very least in the context of a North Korea that is committed to active denuclearization. Words, especially in diplomacy, are difficult to take back, and Trump is on record as being prepared to take unilateral steps never undertaken before.

As the potential for fruitful negotiations has waned, other ideas for addressing North Korean concerns pop up like mushrooms after a dreary rain. One plan for reassuring Pyongyang on a sort of interim basis is to conclude a declaration to “end the Korean war,” that is replace the armistice, a kind of elaborate cease-fire, with a proto-peace treaty that signals preparedness to do exactly what Pyongyang seems to want, namely withdraw U.S. troops from the peninsula. Another idea circulating is diplomatic normalization. If the United States cannot open an embassy in Pyongyang immediately, advocates of this idea argue, perhaps it could establish liaison offices of the kind that served the U.S.-Chinese relationship so well in the years between the Shanghai Accords and the establishment of full diplomatic relations. North Korea already rejected this idea in 2007, and would probably do so again, but these are the sorts of things that come up when one is essentially negotiating with oneself.

Right now, the challenge for the Trump administration is to recreate its “maximum pressure” campaign, which involved unprecedented UN sanctions and an emerging enforcement regime, in the post-Singapore policy context. The last round of these sanctions included holding back refined petroleum to a country without refinery capacity—serious leverage, far more so than, for example, travel bans for people who don’t travel much anyway. It won’t be easy, but a serious diplomatic effort would be a good start to ensure that the countries in the region are prepared to work with Washington to address the North Korean threat.

The Trump administration does indeed need a multilateral North Korea strategy that engages the region. A merely bilateral policy of speaking in real time with the North Koreans and informing everyone else after the fact is not such a strategy. Inevitably it leads to resentments, misinterpretations, and to the inevitable tendency of the international community to demand of both sides equal amounts of supposed reasonableness.

For starters, South Korea, the country that started the 2018 negotiating process, needs to be at the table. It has invested heavily in diplomacy with North Korea and the prospect of failure, looming now, will be far better accepted if Seoul is a full participant in negotiations rather than an anxious bystander.

Japan, too, is a vital ally of the United States and must have a sense that Washington treats it as a full partner on the North Korea issue. Pyongyang, after all, has abducted Japanese citizens, sometimes off the streets of Japan. Neither the Japanese public, nor frankly any public, can accept only vague explanations or accounting of what actually happened with these kidnappings. This does not mean that Japan has no interest in the broader issue of North Korean denuclearization or of the threat posed to its homeland by North Korean missiles. But it does mean that the Japanese public is engaged in a serious and personal way that cannot be ignored.

Even more complex is China’s role. No doubt, Beijing welcomes a diplomatic approach rather than fire and fury, but to have the United States take the lead on talks with Beijing’s neighbor and historic communist partner was too much for the Chinese leadership to endure. As a consequence, a bitter irony of the U.S. initiative has been a Chinese–North Korean rapprochement of the kind that hasn’t been seen in a decade.

Beijing does not want a nuclear North Korea, but neither does it want to be marginalized by the Washington in its own neighborhood.

Those who argue that working with China to resolve the North Korea nuclear issue would be difficult should consider the prospects of working against China. Beijing does not want a nuclear North Korea, but neither does it want to be marginalized by the Washington in its own neighborhood. A sustained and focused U.S. policy toward China, one that calibrates the myriad of issues—including trade—is a challenge that past administrations have met with varying degrees of success. The Trump administration has got to do better if it is to succeed in the goal—shared by China—of denuclearizing North Korea. To castigate China in public for supposedly working against the United States is to set U.S. interests back, rather than to devise a course forward. Instead, Washington and Beijing need to sit down and make clear what their respective interests are (and are not) in the region and work together to hash out the best possible strategy for getting North Korea to yes on denuclearization. Presenting a united front would prevent North Korea from being able to go shopping for initiatives and to explore every crack in the U.S.-Chinese relationship.

Singapore has upped the ante for the United States. The failed aftermath requires that the administration show resolve, a sense of calm, and a renewed dedication to addressing the North Korean nuclear problem. Washington cannot walk away from the threat, but the key to convincing the regional players of that is not to walk away from them, either.