1918: The armored cruiser USS San Diego (CA-6) sank after hitting a mine off Fire Island, New York. San Diego was launched as USS California (ACR-6) at Union Iron Works in 1904. In 1912 California was sent to Nicaragua to protect American interests during the political unrest. On Jan. 21, 1915 San Diego suffered a boiler explosion, while there were no fatalities several were injured. One of the reasons there were no deaths was the courage of two men, Robert W. Cary and Telesforo Trinidad.

Cary, later Rear Admiral, held the watertight door bodily while it was being closed electrically from the bridge, even as steam from the devastated boiler swirled around him. Several men escaped certain death due to his actions. Trinidad returned to the boiler room, even under the threat of further explosions to rescue another man. Trinidad was burned on the face. For their heroism both men received the Medal of Honor.

On July 19, 1918 the San Diego had returned from convoy escort duty when she hit a mine laid by U-156. San Diego went down with the loss of six of her crew. She was the only major warship loss suffered by the USA in World War 1. The wreck remains where she sank.