As the U.S.-Israel war on Iran enters its fourth week and President Donald Trump orders the deployment of thousands of additional sailors and Marines to the Middle East, the troops he is counting on appear increasingly wary of the conflict.

Interviews with active duty soldiers, reservists, and advocacy groups focused on service members found some U.S. troops who are caught up in the war are reporting vulnerability, overwhelming stress, frustration and disillusionment to the degree they may leave the military. The reservists and active duty soldiers spoke on condition of anonymity for fear of retaliation or because they were not authorized to speak to the press.

A military official who is treating service members evacuated from the Middle East to Landstuhl Regional Medical Center in Germany amid Iran’s retaliation said troops are suffering from “inadequate force protection and planning” and already reporting a severe, destabilizing toll from Iranian ballistic missiles and drones that have been repeatedly striking American military facilities. Thirteen troops have been killed amid the war so far, seven due to strikes, and at least 232 have been wounded.

A ground operation would be “an absolute disaster… we don’t have a plan for that,” the official said earlier this week. “We can’t even fully defend a single land base in the theater.”