The United States base at Tower 22 in Jordan is in the middle of a seemingly unending desert, astride the ancient Damascus-Baghdad Highway near the border with Syria. In January it is cold, often rainy and very bleak. Last month three U.S. service members at Tower 22 were killed by a drone launched by an Iranian-backed militia. Their deaths prompted more than 80 retaliatory strikes by the United States against the Islamic Revolutionary Guards Corps and militias operating in Iraq and Syria.

The attack in Jordan was the clear, foreseeable result of our tepid responses to more than 150 attacks against U.S. forces in Syria and Iraq since October. The simple fact of the matter is this: For too long, we postponed dealing with a growing threat to our forces in the region because our troops were able to defend themselves so well. In other words, our troops’ capabilities enabled Washington to minimize the risk they faced — and to avoid making hard choices.

The Tower 22 attack ended that state of play and sparked fresh questions about the safety of thousands of U.S. military personnel stationed in Jordan, Syria and Iraq as the Middle East conflict widens. Last month, the United States and Iraq started talks that could lead to the withdrawal of U.S. troops. Some members of the Biden administration may be considering pulling troops from Syria as well, according to one report.

This kind of talk can be seriously damaging to U.S. interests in the region. It gives hope to Tehran that it is succeeding in its long-term goal of ejecting the United States from the region through its proxy militias. Nothing could be less helpful — or more dangerous to our service members who are already in harm’s way.

Should U.S. troops stay in Syria and Iraq, or should they go? And if they stay, how does American leadership prevent these attacks from continuing? What’s needed now is a presidential decision that has been too long deferred: a firm commitment to keeping our troops in Syria and an additional, nuanced commitment to work with the Iraqi government to find a mutually agreeable force level in that country.

Let’s look first at Syria. It’s become commonplace in Washington to say that the presence of our 900 service members in Syria has outrun our foreign policy. The reality is much more complex than that. The United States entered Syria in 2014 with an international coalition to confront ISIS with our partners, the Syrian Democratic Forces. By mid-2019, we achieved the goal of removing the caliphate as a geographic entity, but remnants of ISIS endured.

Since then, American troops have continued to work with the Syrian Democratic Forces in northeastern Syria to train local defense forces. We have helped the group manage more than 10,000 surrendered ISIS fighters now in prison and the roughly 50,000 people displaced there.

A withdrawal would come with serious risks. Without U.S. support, the Syrian Democratic Forces could struggle to continue to secure the prisons holding ISIS fighters and camps where so many displaced Syrians lead tenuous lives. If enough ISIS fighters are freed and the group has the space to rejuvenate itself, it will lead to fresh threats to Iraq and many other nations. President Bashar al-Assad’s forces, even if buttressed by Russia and Iran, would find it difficult to suppress ISIS.

Our long-term goal in fighting ISIS in this part of the world has always been to get to a point that local security forces will be able to assume primary responsibility for preventing attacks. We have made some progress in Syria, but much remains to be done. It is not yet time to leave.

Next door in Iraq, we have about 2,500 troops, who have been helping train Iraqi security forces to confront ISIS. We’re farther along with this goal than we are in Syria, but there is still a need for us in Iraq. It is reasonable to assume that our troop presence in Iraq will decrease as negotiations continue with the government and will shift to a more normal security cooperation arrangement that will require fewer U.S. forces. But it would be a mistake to withdraw too quickly, as we did in 2011. We also need to bear in mind that a platform in Iraq is a precondition for maintaining our forces in Syria.

As in Syria, our forces in Iraq have been subject to attacks by paramilitary groups that answer to Iran. Negotiating our continued presence there is another complex situation. Iraq’s leaders are in an uncomfortable place. They know they need allied help to train their security forces; at the same time, they face strong pressure from Iranian-sponsored Shiite groups to remove all foreign military presence in the country. The United States ratchets up that pressure by striking Iranian proxy and Islamic Revolutionary Guards Corps targets in Iraq, as it did this month.

In the end, American troops are in Syria and Iraq to prevent ISIS from being able to attack our homeland. By leaving, we could give them the time and space to re-establish a caliphate, increasing our risk at home. We may also face the prospect of being forced to return at a very high cost. There would be negative consequences across the region as well: Our rapid withdrawal would be seen as yet another example of American weakness that adversaries would not hesitate to exploit.

Leaving is not a choice that should made lightly, but staying is not a good choice, either, unless we can end the attacks on our troops. It’s still unclear whether we will be able to do this, and a stream of U.S. casualties will make it increasingly hard to stay. If we want to remain, we must effectively deter, deflect and defeat attacks on U.S. forces by Iranian-backed groups.

We are at an inflection point. Americans have died. Our response must be based not on emotion or a desire for revenge but rather on a cleareyed determination about what is best for the United States. I believe it is best to stay the course and to defend our homeland abroad rather than at home.

Gen. Kenneth F. McKenzie Jr., a retired Marine, was the 14th commander of U.S. Central Command. He is the executive director of the Global and National Security Institute at the University of South Florida. His forthcoming book is “The Melting Point: High Command and War in the 21st Century.”

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