The greatest superpower at the end of World War II was the United States, although it should be noted that the Soviet Union was seen as another great superpower as well.
In the 1994 version of its annual publication, Service and Casualties in Major Wars and Conflicts, the Pentagon put Korean War battle deaths at 33,652 and "other deaths" meaning deaths in the war zone from illness, accidents and other non-battle causes at 3,262. That yields a total of 36,914.
The United States was unprepared for the attack at Pearl Harbor because up until that point America was not involved in the war. It was at that point that we became involved in the war.
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