The United States during the Syrian Civil War, which began in 2011, first supplied the apparently moderate rebels of the Free Syrian Army with nonlethal aid (including food rations and pickup trucks), but quickly began providing training, cash, and intelligence to selected Syrian rebel commanders (see Foreign involvement in the Syrian Civil War#United States).

The United States began surveillance missions on ISIL positions in Syria in September 2014. On September 10, Obama gave a speech indicating his intent to „degrade and ultimately destroy“ ISIL, saying, „I have made it clear that we will hunt down terrorists who threaten our country, wherever they are. That means I will not hesitate to take action against ISIL in Syria, as well as Iraq.“

On September 22, 2014, the United States, Bahrain, Jordan, Qatar, Saudi Arabia, and the United Arab Emirates began to strike targets of the Islamic State of Iraq and the Levant (ISIL) inside Syria, which included the Khorasan group in the Idlib Governorate to the west of Aleppo, and the al-Nusra Front around Ar-Raqqah, as part of the military intervention against the Islamic State of Iraq and the Levant.