FILE - In this Dec. 21. 2017, file photo, Defense Secretary Jim Mattis talks to U.S. Marine Corps troops at a rifle range at Guantanamo Bay, Cuba. For only the second time since 9/11, America’s defense secretary didn’t visit U.S. troops in a war zone during December, breaking a longstanding tradition of personally and publicly thanking service members in combat who are separated from their families during the holiday season. (AP Photo/Robert Burns, File)
FILE - In this Dec. 21. 2017, file photo, Defense Secretary Jim Mattis talks to U.S. Marine Corps troops at a rifle range at Guantanamo Bay, Cuba. For only the second time since 9/11, America’s defense secretary didn’t visit U.S. troops in a war zone during December, breaking a longstanding tradition of personally and publicly thanking service members in combat who are separated from their families during the holiday season. (AP Photo/Robert Burns, File) Credit: Robert Burns

Washington — For only the second time since 9/11, America’s defense secretary didn’t visit U.S. troops in a war zone during December, breaking a long-standing tradition of personally and publicly thanking service members in combat who are separated from their families during the holiday season.

Pentagon boss Jim Mattis, who spent more than four decades in the Marine Corps and deployed to Iraq and Afghanistan, made a five-day trip through the Middle East in early December. He stopped in Kuwait and Pakistan — countries adjacent to Iraq and Afghanistan — but didn’t cross the borders to see troops at war in either country. Last week, he visited troops in Guantanamo Bay, Cuba, and at military bases in Florida, North Carolina and South Carolina, wishing them holiday cheer.

It has been 15 years since a U.S. defense chief didn’t travel to a war zone during the festive season. And the only time a holiday visit was skipped since Americans began fighting in Afghanistan was in December 2002.