Resolute Support Mission (RSM) or Operation Resolute Support was a NATO-led multinational mission in Afghanistan. It began on 1 January 2015 as the successor to the International Security Assistance Force (ISAF), which was completed on 28 December 2014. Pursuant to United Nations Security Council Resolution 2189 of 2014, RSM was a noncombat mission aimed at advising and training Afghan security forces to provide long-term security to the country, under the aegis of the Security and Defence Cooperation Agreement BSA between the United States and Afghanistan, which was originally supposed to run from 1 January 2015 and "shall remain in force until the end of 2024 and beyond" unless terminated with two years' advance notice.

The North Atlantic Treaty Organization, also called the North Atlantic Alliance, is an intergovernmental military alliance of 32 member states—30 European and 2 North American. Established in the aftermath of World War II, the organization implements the North Atlantic Treaty, signed in Washington, D.C., on 4 April 1949. NATO is a collective security system: its independent member states agree to defend each other against attacks by third parties. During the Cold War, NATO operated as a check on the threat posed by the Soviet Union. The alliance remained in place after the dissolution of the Soviet Union and the Warsaw Pact, and has been involved in military operations in the Balkans, the Middle East, South Asia and Africa. The organization's motto is animus in consulendo liber. The organization's strategic concepts include deterrence.