Turkish Incursion into Syria: U.S. Policy Implications

On October 9, Turkish President Recep Tayyip Erdogan announced the start of "Operation Peace Spring," which he stated would target both Kurdish and Islamic State (IS, aka ISIL/ISIS) fighters in northern Syria. Turkey then launched an air and ground assault against Kurdish forces. Turkey's foreign minister has stated that Turkish forces plan to go 18 miles into Syrian territory, and eventually to occupy a corridor along the border. The commander of the Kurdish-led Syrian Democratic Forces (SDF) had stated that the SDF would resist, and fighting has escalated.

The launch of the operation followed an October 6 call between President Donald Trump and Erdogan, after which the White House announced that Turkey would "soon be moving forward with its long-planned operation into Northern Syria," and that U.S. forces would "no longer be in the immediate area." Some Members of Congress then argued that a "precipitous withdrawal" of U.S. forces would benefit Russia, Iran, the Islamic State, and the Syrian regime.

State Department and Pentagon officials subsequently emphasized that roughly 50 U.S. Special Forces personnel had been withdrawn from two outposts to "more secure areas," and that the move did not signal a pullout of U.S. troops from Syria. On October 8, President Trump tweeted, "We may be in the process of leaving Syria, but in no way have we Abandoned the Kurds." He warned that if Turkey took any unspecified steps that he considered "off-limits," he would "totally destroy and obliterate" Turkey's economy, while also inviting Erdogan to Washington in mid-November. Following the start of Operation Peace Spring, President Trump stated, "The United States does not endorse this attack and has made it clear to Turkey that this operation is a bad idea."

Figure 1. Syria–Turkey Border

Source: CRS using area of influence data from IHS Conflict Monitor.

Note: This map does not depict all U.S. bases in Syria.


Since 2014, U.S. forces have partnered with a Kurdish militia known as the People's Protection Units (YPG) against ISIS in Syria. In 2015, the YPG joined with other Syrian groups to form the SDF, comprising the SDF's leading component. Turkey considers the YPG to be the Syrian branch of the PKK (Kurdistan Workers' Party), a U.S.-designated terror group that has waged a decades-long insurgency in Turkey. Ankara has strongly objected to U.S. cooperation with the SDF. U.S. officials have acknowledged YPG-PKK ties, but consider the two groups distinct.

Following an earlier call with Erdogan in December 2018, President Trump announced that U.S. troops in Syria had defeated ISIS and would all be "coming back now." That announcement was gradually walked back, and U.S. officials sought foreign contributions to offset reductions in U.S. force levels that reportedly left just under 1,000 U.S. troops in the country.

Subsequent U.S.-Turkey negotiations over the creation of a safe zone inside Syria led to an agreement in August by Kurdish forces to withdraw from a strip along the Turkish border, considerably narrower than the 20-mile-deep zone Turkey sought. While this agreement led to joint U.S.-Turkey ground patrols and some dismantling of YPG fortifications, Turkish leaders repeatedly criticized the United States for not doing enough to secure the removal of the YPG from the border area.

Turkish Objectives

Turkish officials have publicly stated the two main objectives of military action in northeastern Syria to be countering terrorists (both the YPG and ISIS) and establishing areas for the possible return of Syrian refugees. Turkish leaders consider the YPG's ability to bolster the PKK in Turkey as the top threat to Turkish security, and thus seek to reduce the group's military and political sway. Previous Turkish military operations against IS-held territory (Operation Euphrates Shield in 2016-2017) and directly against the YPG in Afrin district (Operation Olive Branch in 2018) helped limit YPG control across Syria's border with Turkey.

One media report suggests that Turkey's immediate focus appears to be in gaining control over a largely Arab-populated region between the towns of Tell Abiad and Ras al Ain (see Figure 1). Separating the Kurdish enclaves of Kobane and Qamishli could reportedly undermine YPG aspirations for greater autonomy in this border area.

Turkish authorities face domestic pressure to return many of the 3.6 million Syrian refugees in Turkey. Reports claim that Turkey may already have forcibly returned thousands to other areas in Syria, charges Turkish officials deny. Erdogan has warned that if Turkey could not establish a safe zone inside Syria, he would allow refugees to leave Turkey for Europe, notwithstanding an existing Turkey-European Union agreement.

Issues for U.S. Policy

Turkey's military incursion into northeastern Syria presents numerous potential challenges and decision points for U.S. policy, including

  • De-confliction with Turkey. The United States has effectively closed the airspace over northeastern Syria, which could complicate Turkish military operations in a region proximate to at least some U.S. personnel.
  • IS detainees. SDF forces in Syria have approximately 10,000 IS militants in custody at several makeshift prisons in northern Syria, as well as an additional 70,000 IS family members and/or supporters at Al Hol camp. The SDF has warned that forces previously tasked with securing IS prisoners have been diverted to the border.
  • Civilian impact. Turkish military operations carry the risk of civilian casualties and could displace hundreds of thousands.
  • Refugee returns. Forcible refugee returns from Turkey to Syria could violate the 1951 Convention Relating to the Status of Refugees, likely exacerbating humanitarian challenges and potentially generating pressure on U.S. policymakers to respond.
  • Asad-Kurdish reconciliation. Potential coordination between the SDF and the Syrian government, which the United States opposes, could limit future U.S. options to partner with the SDF in counter-IS operations. Observers are debating the relative importance of protecting the SDF alongside other possible U.S. interests.
  • Negative implications for partnership strategies. Successive U.S. administrations have advocated that the United States work with local partners, particularly on counter-terrorism. Current and prospective partners may view the change in policy vis-à-vis the SDF as a negative indicator of U.S. reliability.

Congressional Action

Despite support for the October 6 White House announcement from three Members of Congress, most Members who voiced opinions were critical. Members of both the House and Senate have announced their intention to introduce sanctions on Turkey and/or Turkish officials. How sanctions might affect Turkish actions is unclear. These developments come as Congress considers appropriations and defense authorization measures for FY2020. Turkish operations in northeast Syria may complicate pending proposals to change the authorized levels or permitted recipients of U.S. assistance through the Counter ISIS Train and Equip Fund.