Rodi Said / Reuters

At an Ohio rally in March, President Donald Trump announced that the United States would leave Syria “very soon.” Discussions within the administration after the remarks ultimately led Trump, by September, to commit to a broader plan to remain in the country to ensure the defeat of Islamic State.

Despite that official recommitment, Trump’s words in Ohio did great damage, notably by eroding trust in and among the Kurdish-dominated forces. Before Ohio, the popularity of the U.S.-backed force was actually growing as it drove out ISIS from much of the country and created a de facto safe zone that Bashar al-Assad would not dare to bomb or attack. Widespread goodwill promised to ease the process of creating local and legitimate alternatives to the extremists and the regime in nearly one-third of Syria.

Trump’s decision on Wednesday to fully and rapidly withdraw troops—estimated at 2,200—from Syria should be seen against this backdrop. The White House explained that the surprise announcement does not signal the end of the global coalition’s campaign against ISIS. But even if the effort continues, the goal of keeping ISIS down just got much harder.

For a start, Trump’s claim that ISIS has been defeated is inaccurate. ISIS continues to hold a small but critical pocket of land consisting of a handful of towns along the Euphrates River and the Syrian-Iraqi borders. The campaign to expel the militants from their last stronghold is expected to take a month or two—although the announcement could mean a more aggressive effort that would increase civilian casualties.

Even after the defeat of ISIS in this pocket, the fight will hardly be won. The U.S.-led campaign created new dynamics on the ground, which only the U.S. can now address. For example, U.S. reliance on the Kurdish militia known as the YPG angered Turkey, which views it as an extension of the PKK, the insurgent group that it has been battling in-country for four decades. As the YPG expanded its influence during the fight against ISIS, Ankara shifted its priorities in Syria from backing the opposition in its fight against the regime to aligning with Russia to fight the Kurds.

The timing of Trump’s decision is especially destabilizing, because various parties in the conflict have positioned themselves to attack the areas under YPG control as the campaign against ISIS draws to a close. The end of the campaign means that the U.S. has to work harder, not the opposite, to ensure a peaceful settlement in eastern Syria. Such political support is a fundamental part of finishing the job against ISIS, and this cannot happen without the leverage Washington currently has by being present in Syria.

So far, the U.S.’s presence has prevented Turkey from clashing with the YPG in eastern Syria, as it did in northwestern Syria with Russian approval. Washington does not have the luxury to limit its goal to defeating ISIS militarily and then pulling out. If it simply leaves, new wars will almost certainly be reignited between Turkey and the YPG, the Arabs and the Kurds, and the opposition and the YPG.

Much of the response to Trump’s decision focused on how the move could enable ISIS to return, but the immediate consequences will extend beyond ISIS: The Syrian conflict, after months of quiet, could be rekindled. The end of fighting in most of the country over the past year was possible because of delicate agreements brokered by Russia and various parties and because of the U.S. commitment to the Syrian Democratic Forces (the alliance of Kurdish, Arab, and Assyrian militias led by the YPG). But the peace is still profoundly fragile.

The nightmarish scenario of a return to all-out violence throughout Syria could directly undermine U.S. interests, including by provoking new waves of refugees and emboldening extremists. At this moment, the forces most active against the Syrian regime are predominantly those linked to ISIS and al-Qaeda, because the moderates have already struck deals with Damascus and Moscow. This means that hard-liners will be well positioned to inherit what remains of the rebellion against the regime.

Iraq is a likely victim of the decision, too. Northern Iraq and eastern Syria could now be regarded as one security theater. Even when Syria was stable in the early 2000s, Iraq still suffered from cross-border activities, and U.S. troops had difficulty securing the borders. The situation today is far worse; borders are more porous than ever, and both countries are interdependent from a stability standpoint. If Iraq is important for the U.S., then eastern Syria must also be important.

Americans directly involved in the fight against ISIS understand these challenges, and there has been a broad bipartisan pushback against Trump’s decision to withdraw from Syria. Trump himself blamed the rise of ISIS in 2014 on Barack Obama’s withdrawal from Iraq in 2011. If what Trump wants is to appeal to his base and claim victory against ISIS, there is another way forward.

The next stage in the fight against ISIS requires more political management than kinetic operations, and the U.S. could benefit from a rebranding of the campaign to better define what it takes to ensure the enduring defeat of ISIS in the coming years. This rebranding should involve an announcement to mark the end of one phase of the campaign, namely the territorial defeat of ISIS, and the start of a new phase, which is the long-term effort to build capacity and help locals prevent the return of extremists. The new phase should involve multi-country security support to eradicate ISIS cells and counter its insurgency tactics, a political strategy to manage the transition and resolve differences among competing forces such as Turkey and the Kurds, and economic cooperation to rebuild destroyed areas.

Trump loves branding, and rebranding. Someone should tell him that he can have his rhetoric and stability, too.

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