The US Navy commissioned USS Nautilus, which became the world’s first nuclear submarine.
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The USS Holland (SS-1) became the first modern submarine commissioned for the United States Navy.
Elvis Presley enlisted in the US army.
The United States Marine Corps was founded when two battalions of Continental Marines came together in Philadelphia, Pennsylvania.
The US military policy "don't ask, don't tell" came to an end.
The Wounded Knee Massacre took place.
