People in most countries around the world did not like what the Soviet Union was doing in Afghanistan. They liked the way the Afghan people were fighting them. Some reactions were very serious. US President Jimmy Carter said that the Soviet action was "the most serious threat to the peace since the Second World War". Carter threatened to boycott the 1980 Olympic Games in Russia unless the Soviet Union withdrew its forces by February 1980. It did not do this, and therefore the U.S. boycotted the Games.