U.S. forces in Afghanistan have been authorized by President Obama to retain counter-terrorism authorities even after their combat mission ends there on December 31. Though U.S. troops were supposed to just train, advise, and assist Afghan forces after 2014, they will now likely be involved in offensive operations against the Taliban next year. “A key focus of the United States’ post-2014 mission in Afghanistan will be counter-terrorism, and we will continue to target the remnants of al Qaeda in Afghanistan to prevent an al Qaeda resurgence or external plotting against U.S. targets or the homeland,” a senior U.S. official told NBC News. Troops will also continue to train Afghan forces but will be authorized to “provide combat enabler support” under certain circumstances.