As the US completes its final withdrawal from Iraq, American special forces troops have been diverted to positions in Jordan opposite a Syrian tank concentration building up across the kingdom's northern border.
President Bashar Assad's warned that he would set the entire Middle East on fire if the pressure on his regime to step down persisted.
Syria's other neighbors have taken precautions against this contingency but this is the first time US boots have hit the ground directly opposite Assad's army.
Iraqi sources report that the American units came from the big Iraqi Ain al-Assad air base in the western province of Al Anbar opposite the Jordanian border. This base is in the process of evacuation as the US military drawdown in Iraq approaches completion.