Peace in our time: U.S. officials fear Iran might attack American troops in Iraq

Two scenarios are of particular concern, officials say. One is that a collapse of the nuclear talks could escalate tensions between Iran and the U.S., emboldening Iranian hard-liners and potentially leading to attacks on Americans in Iraq.

The other is that increased U.S. efforts to oust Syrian president Bashar Assad, a close ally of Tehran, could provoke retaliation from Iran. White House officials who oppose greater involvement in Syria’s civil war often cite concern for the safety of Americans in Iraq as a reason for caution, sources said.

In either case, U.S. officials fear, Iran could direct the Iraqi Shiite militias under its control to attack U.S. troops aiding the fight against the Islamic State in Iraq and the Levant.

“The current [nuclear] negotiations likely have a restraining effect, but there are other incentives and national interests at stake for the Iranians,” said a senior U.S. military official. “This is something that we are continually assessing. [Iran’s] history as regional provocateurs and exporters on terrorism demands it.”