U.S. troops are in Syria primarily to prevent the Islamic State (ISIS) from coming back in force and to support local partners who fight those militants. They also serve broader U.S. goals of limiting Iranian and Russian influence and stabilizing parts of eastern Syria.
Main stated mission
The formal mission for U.S. forces in Syria is counterterrorism: stopping ISIS from reconstituting its networks, leadership, and territorial control after the collapse of its “caliphate.” A relatively small number of troops work with local allies, especially the Syrian Democratic Forces (SDF), to conduct raids, gather intelligence, and guard detention sites holding ISIS fighters and families.
Where troops are and what they do
Roughly several hundred to about 900 U.S. personnel operate mainly in Kurdish- led northeast Syria and at the al‑Tanf garrison near the borders with Iraq and Jordan. Their tasks include advising and assisting local forces, securing key areas and routes, and providing a platform for airstrikes and surveillance against ISIS cells.
Other strategic reasons
Beyond ISIS, the presence helps complicate Iran’s effort to move fighters and weapons across Syria toward Lebanon and Israel, and it limits the freedom of action of both Iranian-backed militias and, to a lesser degree, Russia and the Syrian government in the east. The deployment also gives Washington leverage in regional diplomacy and in shaping any eventual security order in eastern Syria.
How and why it started
U.S. ground troops first entered Syria around 2014–2015, under the Obama administration, after ISIS seized large areas during the Syrian civil war. The idea was to use a small American footprint working “by, with, and through” local partners instead of a large-scale occupation, focusing narrowly on defeating ISIS.
Current debates and possible drawdown
There is ongoing debate in the United States about whether the risks of staying—attacks on U.S. forces, legal and political concerns—outweigh the risks of leaving and possibly allowing ISIS or hostile states to fill a vacuum. Recent reporting in 2025 describes gradual troop reductions and consolidation onto fewer bases, with talk of a potential full withdrawal in the next few years, though the timing and conditions remain uncertain.
