Several mortar rounds on Saturday struck an Iraqi air base housing U.S. troops, hours after thousands of Iraqis packed the streets here to mourn two senior military commanders killed in a U.S. airstrike.

In 2007, U.S. commandos watched as a convoy carrying a powerful Iranian military leader made its way to northern Iraq.

For Iranians whose icons since the Islamic Revolution have been stern-faced clergy, Maj. Gen. Qassem Soleimani widely represented a figure of national resilience in the face of four decades of U.S. pressure.