Who did the U.S. fight in World War II?

In World War II, the United States fought against the Axis Powers, which primarily included Japan, Germany, and Italy. These countries had formed a military alliance and were engaged in aggressive expansionism, which led to widespread conflict across multiple continents. The United States entered the war after the attack on Pearl Harbor by Japan in December 1941, and subsequently declared war on Germany and Italy as well.

The U.S. played a crucial role in the defeat of these nations through significant military campaigns and alliances with other countries, such as Britain and the Soviet Union, who were also fighting against the Axis Powers. This collaboration was essential in turning the tide of the war in favor of the Allies.

The other groups mentioned in the other choices were not opponents of the U.S. in World War II. France, Britain, and Australia were allies working alongside the U.S. to defeat the Axis Powers. The Soviet Union and China were also allies against the Axis, though they faced separate challenges outside the context of U.S. opposition. North Korea, Vietnam, and Cambodia were not involved in World War II conflicts against the U.S. but were relevant in conflicts during later years, especially during the Cold War era.