Questions: The United States entered World War II as a result of a direct attack on Pearl Harbor by which nation?

The answer is Japan.

Germany was a major Axis power during World War II, but it did not directly attack the United States. The U.S. declared war on Germany after Germany declared war on the U.S. following the attack on Pearl Harbor.

Italy was also an Axis power and allied with Germany and Japan, but it did not directly attack the United States. The U.S. declared war on Italy after the attack on Pearl Harbor and subsequent declarations of war by Germany and Italy.

Japan directly attacked the United States on December 7, 1941, by bombing the naval base at Pearl Harbor in Hawaii. This attack led to the United States formally entering World War II the following day.

Russia, or the Soviet Union at the time, was not involved in the attack on Pearl Harbor. In fact, the Soviet Union was an ally of the United States during World War II after Germany invaded the Soviet Union in 1941.