Operation Enduring Freedom (OEF) was the official name used by the U.S. government for both the first stage (2001–2014) of the War in Afghanistan (2001–2021) and the larger-scale Global War on Terrorism. On 7 October 2001, in response to the September 11 attacks, President George W. Bush announced that airstrikes against Al-Qaeda and the Taliban had begun in Afghanistan. Beyond the military actions in Afghanistan, Operation Enduring Freedom was also affiliated with counterterrorism operations in other countries, such as OEF-Philippines and OEF-Trans Sahara.
https://en.wikipedia.org/wiki/Operation_Enduring_Freedom