During the first half of the twentieth century, two major international conflicts, World War I and World War II, occurred. Both were fought between major nations. The United States joined both of them in 1941. The United States’ entry into both wars merged both conflicts into one global struggle.

The first World War was a war of territorial acquisition. The Soviet Union and the Austro-Hungarian empire, along with the Germans, tried to take territory. A large military operation, the Blitzkrieg, was used by the Germans. They advanced quickly and used explosive mines to hinder infantry advances across trenches.

The Second World War was the largest and most destructive conflict in human history. It devastated Europe, Asia, and the Pacific. It ended with a total victory of the Allies over the Germans.

The Second World War also drew in the US, Great Britain, and France. The United States entered the war in December 1941. This merged the two conflict into one, and changed the political balance of the war.

The Second World War was fought between the Axis, including Germany, Japan, and Italy, and the Allies, including the United States, Great Britain, and France. It was a devastating war, and the number of casualties varies. In some estimates, between 50 and 80 million civilians died, and between nine and ten million military personnel died.

By the end of the war, every country in Africa had committed to one side or another. It was considered a proxy war. The United States helped bind the different fronts of conflict together, mainly by providing economic aid to Britain and France.