Even the dead insurgents lining the streets and alleys of Fallujah were a threat to the U.S. Marines pushing into the Iraqi city two decades ago.
Troops shot up the often boobytrapped corpses lying ahead of them as a precaution. Enemy snipers hid in the buildings. Others sprung from spider holes and fired from a high-powered Western arsenal that included .50-caliber machine guns, much of it seized from earlier fights.
The initial push on Nov. 7, 2004, marked the start of what would turn out to be the bloodiest battle of the Iraq War, confronting U.S. forces with fighting on a scale not seen since Vietnam.
Twenty years later, memories from the battle, which killed nearly 100 U.S. service members, remain raw for many who fought there. And some continue to grapple with the legacy of what it all meant.