As is now well-known, the United States last night hit approximately 25 targets inside Syria, some of which were directed at ISIL, and some at a group that has only recently been brought to the public’s attention – the Khorasan Group, which is reportedly comprised of al Qaeda militants and led by senior al Qaeda officials from among Usama bin Laden’s inner circle.  According to a letter submitted by the United States to the United Nations on Tuesday, the Administration is justifying the strikes against ISIL as a lawful exercise of collective self-defense of Iraq. The letter then goes on to state that the strikes against the Khorasan Group “address terrorist threats that they pose to the United States and our partners and allies.”

Jennifer Daskal, Ashley S. Deeks & Ryan Goodman, Strikes in Syria: The International Law Framework, Lawfare (September 24, 2014).