President Donald Trump has pulled out of the nuclear agreement with Iran and his administration has begun to re-impose sanctions. The toughest measures would deny access to the U.S. financial system to foreign entities purchasing Iranian crude oil.

However, the administration will grant the full 180-day grace period to allies and partners. Thus, the agreement’s eventual collapse, though it is now likely, is not imminent. Europe will use that time to try to find a way to preserve the deal. Iran will use it to try to drive a wedge through the trans-Atlantic alliance. Israel and Saudi Arabia will relish the Trump administration’s embarking on a possible confrontation with Iran. Countries caught in the middle, such as Iraq, Lebanon, and Yemen, face difficult days ahead.

While the dust settles, Trump will turn his attention to North Korea. The White House believes the president has put down a stern marker. He intends to negotiate with Pyongyang from a position of strength. But the opposite may be true. Trump’s withdrawal will raise resistance from China. His disregard for America’s European allies will rattle South Korea and Japan. One Korean expert admitted to me, during my visit to Seoul last week, that she was more worried about Donald Trump than Kim Jung-un.

Kim will demand more tangible assurances from Trump than former president Barack Obama provided to Tehran. Critics of the Iran nuclear deal note that it was not a treaty and was not approved by Congress. True, however Trump is likely to find that his options with Congress are no more appealing than Obama’s were.

The agreement with Iran requires a 98 percent reduction of its uranium stockpiles and a two-thirds reduction of its installed centrifuges. Things will not be the same with the regime in North Korea. Yes, the dismantlement of the North Korean nuclear program is highly desirable, but to imagine Kim voluntarily surrendering his estimated 10–20 nuclear weapons is to engage in fantasy. The likelihood of failure is high. This sets the stage for a dangerous standoff on the Korean peninsula that could make Iran feel like a walk in the park by comparison.

And what of the Iran deal itself? Sanctions are a tool, not a cure-all. In the past, in partnership with Europe and under the political cover of several United Nations Security Council resolutions, U.S. sanctions helped to leverage a settlement with Iran. Historians will debate the agreement’s merits, however one thing is beyond dispute: In nine years of negotiations, Iran’s nuclear advances sometimes lost speed but were never undone.

The primary target of U.S. secondary sanctions is not Iran itself, but foreign financial institutions that trade with it. The Trump administration will demand that countries choose between the U.S. financial system and Iran’s. Many countries, perhaps most, will reluctantly adhere to Trump’s demands.

But the process will be tedious and messy. This time around, the Trump administration enjoys neither trans-Atlantic unity nor international legitimacy. Senior administration officials will log long hours flying around the world to lecture leaders—many of whom believe Trump’s withdrawal to be a material breach of an agreement which was working—on the dangers of Iran’s nuclear program. 

Some of these leaders, including American friends, may challenge the validity of secondary sanctions, citing violations of World Trade Organization obligations and the July 2015 UN Security Council resolution endorsing the Iran agreement. The blow to trans-Atlantic relations is not beyond repair, but it is significant. French President Emmanuel Macron invested significant political capital into building a rapport with Donald Trump. He has little to show for it. It is difficult to imagine another major European leader following in his footsteps.

On the other hand, Trump is a performance artist focused on the theatrics of his announcements rather than the substance of his policies. His bombast often appears less menacing in retrospect. Early in his tenure, he withdrew in a huff from the Paris climate accords and the Transpacific Partnership (TPP). Not one of the other 193 signatories followed his lead in leaving the Paris accords. And amid tit-for-tat trade pronouncements by Washington and Beijing, Trump is contemplating rejoining the TPP.

Trump enjoys considerable discretion in re-imposing sanctions. So it is not inconceivable that the Iran agreement will limp on. Whatever one thinks of the Obama administration’s approach, the endgame was clear. The economic pressure against Tehran was slowly raised. Space was created for a tradeoff between U.S. sanctions and Iranian centrifuges. In contrast, Trump’s withdrawal announcement, though it was hardly a surprise, offered no Plan B. Neither did the president outline a clear objective.

Is Trump seeking a new agreement with Iran? Is he seeking the complete eradication of the Iranian nuclear program? Or is he seeking regime change in Iran? One could plausibly imply from his remarks any, or all, of these results. Sanctions alone will achieve none of them.

The next moves are likely to play out over several months. A number of plot twists are left to be revealed. War and nuclear crisis are far from inevitabilities. But after Trump’s announcement on Tuesday, neither are they inconceivable.