Operations in Afghanistan enter new phase as US Marines deploy in country, setting up at an expeditionary base dubbed Camp Rhino. (Navy SEALs first secured Rhino on Nov. 21.)
The U.S. began extensive air and artillery strikes against Islamic State group targets in Syria on Dec. 19 in retaliation for the killing of three Americans on Dec. 13 by a gunman affiliated with ISIS, U.S. officials said.
