Pentagon officials said they have no evidence of the widespread ethnic cleansing that many feared—at least, they stressed, not yet. Some believe both Iran and Iraq understand such attacks could lead the U.S.-led coalition, and the air support that comes with it, to evaporate. Indeed, suspending the U.S. training program for the Iraqis forces and scaling back to counter-terrorism is the most likely immediate U.S. response should ethnic cleansing begin. Some noted that Iraqi Shiites repeatedly refrained from retaliatory attacks in the face of daily bombings by Islamic State forbearer al Qaeda in Iraq during the U.S. occupation, in part, because they understood it hurt their long-term prospects. Sure

As Shiite-dominated forces have moved through Tikrit, “They have shown a significant amount of restraint and discipline,” a U.S. defense official told The Daily Beast.

Still others said such assessments are too optimistic given that the Iranian-backed Iraqi forces have just started to reach Tikrit’s densest population centers. Still others note that the forces may not be conducting such attacks because most of the civilians who would be targeted fled the city for places like the northern Kurdish-dominated city of Irbil.

And it remains unclear whether the ISIS fighters who once were entrenched in Tikrit are still there.

 “Let’s see what happens when they are in the heart of Tikrit,” a second defense official told The Daily Beast.