About the authors
Ilan Goldenberg is a senior fellow and the director of the Middle East Security Program at the Center for a New American Security.
Nicholas A. Heras is a fellow in the Middle East Security Program at the Center for a New American Security.

President Barack Obama shakes hands with President-elect Donald Trump in the Oval Office of the White House on Nov. 10, 2016. (Pablo Martinez Monsivais/Associated Press)

Last week, Secretary of State Rex Tillerson delivered a speech that after a year in office finally laid out a new strategy for Syria. The part that’s getting the most attention is his unequivocal declaration that the United States would maintain an indefinite military presence in Syria, stating, “The United States will maintain a military presence in Syria focused on ensuring ISIS cannot reemerge.”

It doesn’t square with President Trump’s “America first” posture, but it’s the right call.

It also represents an acknowledgment that in Syria, Trump is using President Barack Obama’s playbook. So far, it’s working out pretty well for him.

President George W. Bush deployed hundreds of thousands of troops during the Iraq War. It was costly, took years to bear fruit and was politically unsustainable. Early in his presidency, Obama sought to disengage militarily from Iraq altogether, which backfired by contributing to the governance vacuum that facilitated the rise of the Islamic State.

Trump campaigned against both in 2016, deriding Bush as too eager for war — “Iraq was a big, fat mistake” — and casting Obama as weak, and the “founder of ISIS.”

But over the past three or four years, Obama and Trump have inadvertently teamed on a strategy in Iraq and Syria that has it right: Muddle through with a smaller U.S. investment that keeps the worst from happening but also keeps America out of Middle Eastern quagmires. This is far from a perfect solution. But it happens to be the best one that we have.

Trump has taken credit for recent military gains against the Islamic State, furthering the narrative that he’s responsible for turning things around. In reality, his administration has wisely picked up where Obama’s administration left off and stayed the course.

Their combined approach can keep Syria stable enough to stem the flow of refugees, which has brought tremendous political pressure and instability to U.S. partners in the Middle East and Europe. And it can prevent the reemergence of the Islamic State or similar groups, which would again threaten Western nations and necessarily draw us back to the Middle East in larger numbers.

A few troops go a long way

What the United States has found since 2014 is that a small force of a few thousand U.S. troops can make a meaningful difference. It acts as a force multiplier by training and mentoring local forces, providing them with air and logistical support, and maintaining a forward operating presence for difficult counterterrorism missions.

The capture of Raqqa, the culmination of a three-year campaign in Syria, required a U.S. force level that ranged from about 500 to 2,000 troops, with local partners, which has been estimated at around 50,000 fighters, carrying much of the load. Local Syrian partners provided the bulk of the force that ripped territory away from the Islamic State, with U.S.-led coalition advice, air power and artillery support. This model partnership has been so successful that Gen. Raymond Thomas, who leads the U.S. Special Operations Command, stated in July, “this thing rolled from just a couple thousand that we knew early on to now a 50,000 person force that … has taken every March objective we’ve had so far.”

Stabilization takes time

The United States has successfully marshaled a broad international coalition of 73 nations that provide support for military activities against the Islamic State, work to counter pathways for terrorists to finance, recruit and mobilize, and to assist in the rehabilitation of areas that had been conquered from the Islamic State and humanitarian assistance to their local populations. Last year, for example, the Global Coalition against Daesh (the Islamic State) announced that France would contribute $12.4 million to provide clean water, remove land mines, provide health care and distribute food assistance to the population of the devastated city of Raqqa. But that support will quickly wane if the U.S. commitment is perceived as fleeting.

The massive task of stabilization, rehabilitation and reconstruction in Syria after seven years of civil war will require time and patience. The Syrian Democratic Forces (SDF) — America’s most important partner in this struggle — don’t have the capacity or resources to address all the challenges of building stability, by themselves, in territory previously occupied by the Islamic State. No matter what, Syria won’t be transformed into a Jeffersonian democracy overnight, but an American presence can meaningfully improve the situation.

Already the United States and its partners have set to rebuilding Raqqa and supporting the nascent system of governance being established there, and in the strategic city of Tabqa, by the SDF in the zone it now administers. This can only take place under the shield provided by the presence of the U.S. military, which is helping form a proposed 30,000-person Syrian security force constructed from the building block of the SDF.

This may sound a lot like traditional, expensive and impractical nation-building — and in some ways it is. But it is being done in a more circumspect, pared-down fashion, with a significantly smaller military requirement that doesn’t seek to remake Syrian society but simply ensure a baseline level of stability that prevents a reversion to civil war. As one British general told The Washington Post’s David Ignatius: “This is not a work of beauty. This is pragmatism.”

The Islamic State isn’t done

Despite losing control of Raqqa and Mosul, the Islamic State, now concentrated in a few small pockets in Syria and Iraq, is still capable of a range of attacks, including against local governing councils, security forces and critical infrastructure, including roads, dams and oil and gas wells. The last several months have seen terrorist attacks in Iraq and Syria. The Islamic State has signaled that attacks of this kind will be part of its strategy going forward in its effort to sustain an insurgency.

Without continued U.S. support, Syrian and Iraqi forces won’t be able to contain this threat. Particularly in Syria, where government forces are absent from large parts of the country and local militia dependent on the United States provide most of the security. The investment in building up the capacity of these local partners will probably take years of a small but meaningful U.S. footprint, but if we leave prematurely, as we did in Iraq in 2011, the conditions will exist for the Islamic State to reconstitute its strength, forcing Western powers back into Syria in larger numbers for a much more difficult and expensive military campaign.

We need the bargaining chip

The United States has a vested interest in a viable political agreement that ends the Syrian civil war. Only such an arrangement can close the security and governance vacuums in Syria that create the terrorist safe havens and refugee outflows that threaten our interests. But shaping that outcome requires leverage, and a precipitous withdrawal would leave Trump or a future president with very little in their dealings with Russia, Iran and Syria.

Syrian President Bashar al-Assad has survived, but he presides over an enfeebled regime. His maneuvering room is still limited, especially with a weak domestic economy. It’s unlikely that the regime’s allies, either Iran or Russia, will commit the resources to fund the reconstruction of Assad’s statelet, never mind bankrolling the reconquest of the large areas of the country that remain outside of his rule. But if the United States leaves now, Assad will try to reconquer the entire country, anyway. This will lead to more of the violence that has left hundreds of thousands of Syrians dead. If the United States stays, even in small numbers, we can deter Assad and his allies from retaking this territory — they have shown little interest in picking a direct fight with the United States. Local partners, in turn, will have more leverage to negotiate a settlement where Syria remains fragmented.

Be honest with Americans

If the current administration is going to pursue this long-term indefinite commitment, it should not hide that from the U.S. public. Tillerson’s speech was clear, but it gained relatively little attention. He and Trump must be transparent about U.S. force levels and the open-ended nature of their deployment — right now we have roughly the right force level in Syria for this mission, which should not increase beyond a few thousand.

Administration officials, up to and including the president, should also go to Congress, explain their rationale and plan, and request a new Authorization for the Use of Military Force to support this long-term mission. And it should build a military that in the long run can sustain the types of missions we are arguing for in Syria instead of putting the burden on a small number of Special Operations forces who are being deployed again and again to deal with this, and similar challenges, around the world. The Pentagon has already started to make some progress in this direction by establishing “advise and assist” brigades, which are specifically designed for this type of role.

The U.S. public narrowly supported Trump’s 2017 missile strikes in Syria and, in a poll in April, supported creation of a Syria no-fly zone, with 63 percent saying the United States should do more to help bring an end to the Syrian conflict. What the public is unlikely to support is a large deployment of U.S. forces like those in Iraq and Afghanistan in the past two decades.

It may have been more politically satisfying for Trump to break completely with Obama, abandon Syria to the Russians and Iraq to the Iranians, bring remaining forces home and declare a peace dividend, but picking up where Obama left off and continuing to muddle through has been better for Syrians and Americans.