In the past month, the United States directly struck Bashar al-Assad’s forces and the Shiite militias that support them at least four times. The most notable of these to date took place June 18, when an American F-18 shot down a Syrian fighter plane. Yet, the progression of the campaign against the Islamic State risks plunging the United States into a complex regional conflict they should have every reason to avoid.

With the coming recapture of Mosul in Iraq and the assault on Raqqa in Syria, the Islamic State group is on the verge of losing its strongholds in territory that it had conquered at the height of its power in June 2014. But the fight against the terrorist organization is not finished.

Some of its troops and leaders have relocated to the Deir ez-Zor province. The U.S. military has begun hunting them down because it is concerned about leaving this region in eastern Syria, which borders Iraq, in the hands of the terrorist group.

The Temptation to Confront Tehran

Thrust into an operation to recapture Syrian territory, Bashar al-Assad’s troops and their allies, Shiite militias supported by Tehran, are also active in this region. As a result, this next phase of the fight against the Islamic State group’s army is likely to make the U.S. a player in the vast regional conflict between Sunnis and Shiites, in which Syria has become one of the main theaters.

Barack Obama, like George W. Bush, was very careful not to involve Washington in this conflict between Saudi Arabia and Iran. Donald Trump seems determined not to exercise the same caution. During his speech in Riyadh at the end of May, he put himself clearly in the Sunni camp led by Saudi Arabia and praised their efforts to isolate Shiite Iran.

Some members of his administration, notably Ezra Cohen-Watnick and Derek Harvey, respectively senior director for intelligence programs and chief Middle East adviser at the National Security Council,* even consider developments in Syria as an opportunity to confront Tehran and its allies.

Their goal is to make sure that Iran does not become the dominant regional player by amassing territory covering Iraq, Syria and Lebanon.

This hard line is not, however, shared by others in the Trump administration. Secretary of Defense James Mattis, as well as military officials and diplomats, believe that they are endangering the fight against the Islamic State group. American troops deployed in Syria as well as in Iraq could be subjected to reprisals from Shiite militants supervised by the Iranian Revolutionary Guards.

In the worst-case scenario, escalating tensions between Washington and Tehran could lead to the abandonment of the nuclear accord, signed in July 2015, and thus reopen the possibility of war between the U.S. and Iran.

Although the White House is re-evaluating U.S. policy toward Iran, it is hoped that Donald Trump will not yield to the temptation of the hard line.

More fundamentally, the risks generated by the progressing fight against the Islamic State group highlight the dangers of resorting to force without strategy or political vision. In this regard, Obama is as much at fault as Trump, and the coalition partners against the Islamic State group are as much at fault as the U.S. that leads them.

Since 2014, this coalition’s only goal has been to destroy the terrorist organization. Now that the Islamic State group is about to lose most of its territory, no serious reflection seems to have taken place in Washington or in the capitals of the countries most involved in the future of the Middle East.

The stakes are, however, colossal. What must be done to end the civil wars in Syria and Yemen? How will the disputes between rival regional powers be managed? What is the status of the regions controlled by Kurds, which are at the heart of the fight against the Islamic State group, in Iraq and Syria?

It is only by providing answers—and they certainly won’t be obvious—to these key questions that the United States and its partners can prevent a volatile situation from degenerating into a widespread conflict.

*Editor’s Note: Derek Harvey’s title, as listed on LinkedIn, is Special Assistant to the President, Senior Director for the Middle East.