KABUL, Afghanistan (AP) — The killing of an American serviceman in an exchange of fire with allied Afghan soldiers pushed U.S. military deaths in the war to 2,000, a cold reminder of the perils that remain after an 11-year conflict that now garners little public interest at home.

The toll has climbed steadily in recent months with a spate of attacks by Afghan army and police — supposed allies — against American and NATO troops. That has raised troubling questions about whether countries in the U.S.-led coalition in Afghanistan will achieve their aim of helping the government in Kabul and its forces stand on their own after most foreign troops depart in little more than two years.