U.S. forces conducted live-fire exercise in Syria

Action designed to warn Russians to stay away from American base

U.S. Marines conducted a live-fire, aerial assault exercise in southern Syria on Friday designed to warn Russian and other military forces to stay away from an American base there.

The exercise, involving a company-size unit, came amid rising U.S.-Russia tensions across the Syrian battlespace. The Trump administration has warned both Russia and the Syrian government against a planned offensive in Idlib province in northwest Syria, the largest remaining pocket of rebel fighters who have tried, and failed, over the past seven years to oust President Bashar Assad.

In support of the Idlib operation, Russia has deployed a significant naval presence in the eastern Mediterranean, with weaponry capable of reaching across Syria.

The Marine exercise took place near the U.S. garrison at Tanf, along the Syrian-Iraqi border near Jordan, around which the Americans have long declared a 35-mile deconfliction zone off-limits to others. It followed a Russian notification, and U.S. rejection, of a plan to enter the zone to pursue “terrorists.”

“The United States does not seek to fight the Russians, the government of Syria or any groups that may be providing support to Syria in the Syrian civil war,” Lt. Col. Earl Brown, a U.S. Central Command spokesman, said in a statement. “However, the United States will not hesitate to use necessary and proportionate force to defend U.S., coalition or partner forces.”

The garrison has served as a launchpad for U.S. counterIslamic State operations and a U.S. Special Operations Forces training facility for Syrian fighters aiding in that effort. The zone also lies astride a major transport line between Tehran and Damascus, and control of the area has long been a goal of the Syrian government and its Russian and Iranian allies.