January 31, 2019 |

Midterm Assessment: Syria

Current Policy

In December 2018, President Trump ordered the withdrawal of all U.S. troops from Syria. “We have won against ISIS. We’ve beaten them, and we’ve beaten them badly,” Trump announced, “Now it’s time for our troops to come back home.”1

The president’s decision amounted to a complete and sudden reversal of the policy his principal advisers had developed, which relied on the presence of roughly 2,000 U.S. troops and their local partners to crush the remnants of the Islamic State. The president’s advisers also sought to expel all Iranian-controlled forces from Syria while supporting UN-led negotiations to end the Syrian civil war. The U.S. military mission in Syria does not include offensive operations against the Iranian-controlled forces fighting on behalf of the Bashar al-Assad regime, but the presence of U.S. troops and their local partners generates substantial diplomatic leverage.

As a candidate in 2016, Trump made clear his aversion to continued involvement in Syria for any purpose other than defeating the Islamic State. “I don’t like Assad at all, but Assad is killing ISIS. Russia is killing ISIS. And Iran is killing ISIS,” he said.2 Surprisingly, Trump then chose in April 2017 to punish the Assad regime’s use of chemical weapons by launching 59 cruise missiles at military targets in Syria. A year later, he launched a second round of airstrikes after Assad used chemical weapons again.

In 2017, the U.S. focused on defeating the Islamic State, whose “capital” of Raqqa in northern Syria fell in October to the U.S.-backed Syrian Democratic Forces (SDF), in which Kurdish fighters play an outsized role. Trump sought to avoid further entanglement by reaching an agreement with Russian President Vladimir Putin for Russian troops to monitor a ceasefire that would prevent Assad’s forces as well as Iran and its proxies from approaching the Syrian border with Israel in the Golan Heights.

In early 2018, the administration began to address the long-term threat posed by Iran’s military presence in Syria. By maintaining troops in the northeast, the U.S. could prevent a resurgence of the Islamic State while keeping a resource-rich and strategically significant part of the country out of the hands of Assad and Iran. Then, in March, the president unexpectedly announced at a public rally that the U.S. would be leaving Syria “very soon.” “Let the other people take care of it now,” Trump said, “We are going to get back to our country, where we belong, where we want to be.”3 On the advice of his national security team, Trump quietly postponed consideration of a withdrawal.

In the summer of 2018, Russian forces, Assad’s troops and Iranian-backed militias violated the ceasefire Trump had negotiated with Putin, in the process deliberately bombing hospitals and civilian targets once again. Top administration officials made clear the U.S. would not hand Syria over to the Assad-Russia-Iran coalition. National Security Adviser John Bolton asserted in September, “We’re not going to leave [Syria] as long as Iranian troops are outside Iranian borders.”4

The president reportedly made the decision to withdraw from Syria during a phone call with Turkish President Recep Tayyip Erdogan. Trump’s principal advisers argued that the withdrawal would be a serious mistake, with Secretary of Defense James Mattis ultimately resigning shortly after the president publicly announced his decision. Moreover, Trump did not inform either congressional leaders or foreign allies before his announcement, nor did the Pentagon have time to plan how it would withdraw the troops or continue operations against the Islamic State without a presence in Syria. The timeline for the U.S. withdrawal from Syria remains uncertain for now, although the Pentagon announced the process has begun.

A fighter of the Syrian Democratic Forces (SDF) stands in an empty street in the western neighborhood of Jazrah on the outskirts of Raqqa on October 30, 2017 in Raqqa, Syria. (Photo by Chris McGrath/Getty Images)


President Trump justified his decision to withdraw from Syria by erroneously and repeatedly asserting that the Islamic State had been defeated. Rather than recognizing the low cost and high impact of the mission in Syria, the president described it as a waste of soldiers’ lives and taxpayer dollars. Instead of acknowledging that America’s Kurdish and Arab partners fought a bloody ground war against the Islamic State, Trump suggested that only U.S. troops were engaged in fighting.

The process by which Trump arrived at his decision was also deeply flawed. He reversed a long-standing policy within a matter of days, leaving his own administration scrambling to contain the fallout.

The process by which Trump arrived at his decision was also deeply flawed. He reversed a long-standing policy within a matter of days, leaving his own administration scrambling to contain the fallout. The decision blindsided allied nations with troops in Syria as well as local partners who continue to suffer heavy casualties while fighting the Islamic State. Trump’s secretary of state, secretary of defense, and national security adviser all opposed the withdrawal. While a commander-in-chief has the right to overrule his advisers, Trump ignored the serious concerns they raised.

In addition to damaging the campaign against the Islamic State, the withdrawal from Syria undermines the president’s own strategy “to counter the [Iranian] regime’s destabilizing activity and support for terrorist proxies in the region.”5 The Assad regime plays a central role in what Iran calls its “axis of resistance.” For decades, Tehran has relied on Damascus as a conduit to pass funding and weapons to Hezbollah, enabling it to dominate Lebanon and prepare for a devastating war with Israel. In addition to protecting Assad, Iran is also building up its offensive capabilities in Syria so it can attack Israel directly.

At present, Iran relies mainly on air transport to bring men and materiel into Syria, but has begun to build a “land bridge,” or ground corridor, through which it could project power from western Iran to the Mediterranean. Effective U.S. control of northeast Syria blocks one potential route for the land bridge. The U.S. and its local partners also have a base further south at al-Tanf, along the Syrian-Iraqi border, which prevents Iran from establishing control of the main highway from Baghdad to Damascus. A withdrawal opens these routes to Iran and its allies.

A retreat from Syria would also provide substantial benefits to the Turkish president, an avowed Islamist with a record of human rights abuses. Erdogan has already disrupted the campaign against the Islamic State multiple times by launching military operations against the Syrian Kurds, and has threatened another offensive. Trump argues that the U.S. can trust Erdogan to prosecute the war against the Islamic State in Syria, yet it is doubtful whether the Turkish president has either the will or the ability.

The withdrawal from Syria also benefits Russia, which flagrantly violated the ceasefire to which Trump and Putin personally agreed last year. Russia has a strong interest in supporting Assad’s effort to reassert control over northeast Syria, where more than 90 percent of Syria’s oil is located, as well its most productive agricultural land. The more self-reliant Assad becomes, the less Russia must invest in supporting him. The same is true of Assad and Iran.

Trump has often criticized his predecessor for a reckless and premature withdrawal from Iraq in 2011 that contributed directly to the rise of the Islamic State. He is now on the precipice of repeating that error in Syria. Trump initially announced the immediate departure of all U.S. forces, but administration officials soon extended the timeline, until Trump himself said that there is no date certain for the U.S. departure. Nonetheless, Trump insists his original decision has not changed. What this means in practice remains uncertain.


President Trump was right when he said in 2017, “Conditions on the ground — not arbitrary timetables” should be the basis for any withdrawal. “America’s enemies must never know our plans or believe they can wait us out,” he added.6 Any withdrawal now should also be conditions-based.

  1. Prior to withdrawal, complete the training of local Kurdish and Arab forces so that they can finish the war against the Islamic State and prevent its resurgence. The Pentagon projects a need for 40,000 trained fighters, of which it has trained 8,000.7 The administration should also establish reliable processes for providing these fighters with the weapons, air support, and intelligence needed to defeat the Islamic State.
  2. Prior to withdrawal, secure a commitment from Turkey not to attack the Syrian Kurds again. Erdogan is reportedly resisting any constraints, but Washington should hold firm. In return, the U.S. should guarantee that the Syrian Kurds will not aid or assist the Kurdistan Workers’ Party (PKK), the Kurdish terrorist organization in Turkey.
  3. Encourage the UK, France, and other allies to establish a long-term partnership with the Syrian Kurds. In the absence of Western support, the Syrian Kurds will have to turn to Russia and Iran for protection from Turkey. The likely price for such protection will be granting Assad access to oil, gas, and other resources in northeast Syria, which would alleviate his dire financial situation.
  4. Even if conditions allow a withdrawal from northeast Syria, maintain a contingent of Special Operations Forces at al-Tanf. The base at al-Tanf sits astride the optimal route for Iran’s land bridge to the Mediterranean. The U.S. should also ensure that the UN can provide unimpeded humanitarian relief to the refugee camp at Rukban, a short distance from al-Tanf. Russia and Assad have often blocked this relief in order to destabilize the area and push out U.S. forces. A reliable flow of aid could prevent a grave humanitarian crisis while maintaining positive relations between U.S. forces and the Rukban population.
  5. Maintain U.S. troops and bases in Iraq. It is much less efficient to conduct operations against the Islamic State in Syria from bases in Iraq, yet still far preferable to conducting them from even further away. The president should ask the Pentagon to assess whether additional resources will be needed should the force in Iraq assumes responsibility for operations in Syria.
  6. Intensify the campaign of economic pressure against the Assad regime, thereby raising the cost to Iran and Russia of propping it up. The Treasury Department should vigorously enforce sanctions that prohibit Iran from exporting oil to Syria via tanker. It should also investigate and sanction the new generation of businesspeople, like Samer Foz, as well as banks that help Damascus evade sanctions. Furthermore, Treasury should intensify targeting of those who direct or enable Assad’s human rights violations. The U.S. should also investigate, reform, and monitor the UN humanitarian aid process, which Assad manipulates to support his war effort. It should also pressure Arab partners to stop normalizing relations with Assad prior to a peace settlement.
  7. Support Israeli efforts to degrade Iranian military infrastructure in Syria and prevent the transfer of advanced weapons to Hezbollah. Employ U.S. intelligence, surveillance, and reconnaissance assets to support Israeli missions. Prepare to resupply Israeli munitions, if necessary. Communicate to Russia that it should refrain from interference in Israeli operations against Iranian targets. Consider additional support for Israeli missile defense efforts, such as increasing the rate of production for Iron Dome interceptors.
  8. Communicate to Assad that there will be concrete and escalating costs for any use of chemical weapons. If Assad employs them again, the U.S. should destroy his remaining air forces and air defenses.