Air Force Secretary James G. Roche announces his resignation. He has served in the top USAF civilian post since June 1, 2001 and will officially leave on Jan. 20, 2005.
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.

