More than a decade ago, photographer Ed Freeman set out to capture the gay rights struggle in a photograph for the cover of Frontiers, a gay magazine. To do so, he relied on an image — the flag-raising at Iwo Jima — that has been imitated and adapted countless times since it was captured in the midst of one of America’s bloodiest battles.

The photograph was taken Feb. 23, 1945, four days into an operation that would rage for more than a month. Associated Press photographer Joe Rosenthal snapped the image as five Marines and a Navy corpsman raised an American flag on Mount Suribachi, the highest summit on the Pacific island. Within weeks, three of those Marines were killed in combat, putting them among the 6,821 American fatalities on Iwo Jima. An additional 19,000-plus U.S. troops were wounded, and more than 18,800 Japanese troops also died.

Rosenthal’s photograph received a Pulitzer Prize, and became the centerpiece of a multi-billion dollar war bond effort. It also inspired the Marine Corps War Memorial, the equally iconic bronze monument at the entrance to Arlington National Cemetery that was erected in honor of all Marines killed in combat. In short, Rosenthal’s image became — and remains — a spiritual force.