In 1943, he joined the United States Maritime Service as a photographer and served as a warrant officer documenting life aboard ship in the British Isles and North Africa.

In 1944, he rejoined the Associated Press and followed the United States Army and U.S. Marine Corps in the Pacific Theater of Operations as a war correspondent at Hollandia, New Guinea, Guam, Peleliu, Angaur, and Iwo Jima.

Louis Lowery, a photographer with the Marine publication Leatherneck who was coming down the volcano after an enemy grenade explosion on top had knocked him off his feet and broke his camera.

Lowery told them the view was good from the summit, and Rosenthal convinced Genaust and Campbell to continue to take him to the top with them since they were armed.

[5] On the high and windy summit of Mount Suribachi, Rosenthal discovered a group of Marines attaching a large flag to a length of steel pipe.

[5] To make sure he had a worthwhile photo to send to the AP, Rosenthal took another black and white photograph showing four of the second flag-raisers steadying the flagstaff and waiting for the bottom of the pipe to be more secured with rocks; and afterwards a rope.

When that was done, Rosenthal gathered a group of sixteen Marines and two Navy corpsmen around the base of the flagstaff for a posed shot (called the "Gung Ho" photo) which included First Lieutenant Harold Schrier, the only officer on the summit, who had volunteered to take the 40-man patrol up Mount Suribachi that morning to seize and occupy the crest and raise the battalion's flag.

[8] Wire services flashed what would become a Pulitzer Prize–winning photograph around the world in time to appear in the Sunday newspapers on February 25, 1945 (Lowery's photos weren't released until late 1947).

After the battle for Iwo Jima was over and won, the photo was used for posters in war bond drives through over 30 cities from May 11 through July 4, 1945, which raised $26.3 billion.

On February 23, 1945, a bespectacled Mr. Rosenthal made a picture of five U.S. Marines and one U.S. Navy corpsman that immortalized the American Fighting spirit during World War II and became an everlasting symbol of service and sacrifice, transcending art and the ages.

On Iwo Jima, Japan, short of breath from climbing the 546-foot volcano, Mr. Rosenthal, in haste, stood on top of shaky rocks in search of the best graphic composition.

As the six men hoisted an iron pole and the American flag unfurled in a smart breeze for all to see, Mr. Rosenthal captured the precise moment, unaware, until much later, of its significance.

[14] Reporters extensively interviewed Rosenthal after September 11, 2001, when Thomas E. Franklin shot a similar iconic photograph, Ground Zero Spirit, depicting the raising of the flag by three firefighters at the World Trade Center.