Al-Tanf is a U.S. military base in a part of the Rif Dimashq Governorate, Syria, which is controlled by the Syrian Free Army. It is located 24 km west of the al-Walid border crossing in the Syrian Desert. From Wikipedia
Increasing Iranian-Backed Attacks Coincide with Rising U.S.-Israel Relations; Special Forces, Navy Carrier Groups, and Fighter Jets Deployed in Response