America won 0 gold medals at the 1980 Moscow Olympics. The United States did not send its athletes to compete after President Jimmy Carter announced a boycott in response to the Soviet Union’s invasion of Afghanistan in December 1979.
The boycott meant that the United States had no official team competing in the Summer Games held in Moscow from July 19 to August 3, 1980. Without American competitors, the country could not win Olympic medals in the usual national-team sense. The Soviet Union topped the medal table, winning 80 gold medals and 195 medals overall.
The boycott was part of the Cold War’s growing political tension. More than 60 countries joined or supported the action to varying degrees, although participation rules differed and some athletes from boycotting nations competed independently or under other arrangements.
This answer refers to the 1980 Summer Olympics in Moscow. It should not be confused with the 1980 Winter Olympics in Lake Placid, United States, where American athletes did compete and the U.S. ice hockey team famously defeated the Soviet team in the “Miracle on Ice” game.