Operation Downfall was the largest invasion force ever assembled in history, designed to launch a 2.5-million-man assault on the Japanese mainland. Japanese intelligence correctly guessed the time and ...

The Soviet Union built the largest nuclear bomb ever — but at the last moment, its power was cut in half, turning it into one of the "cleanest" bombs in history. Here’s why Tsar Bomba was never ...

Aug. 5 (UPI) --Remembrances in Japan, the United States and elsewhere mark the 80th anniversaries of the only instances of atomic weapons being used in military conflict and against civilian ...