During World War II, which country, Germany and the United States, declared war on each other first?

After the Pearl Harbor incident, the United States declared war on Japan, but the U.S. Congress was divided on the declaration of war on Germany and the opinions were not unified.

But the historical situation is that Germany was the first to declare war on the United States. There are many opinions. First of all, many people in Germany advised Hitler not to declare war on the United States.

Personal opinion:

1. Germany, Japan and Italy are Axis powers. The United States declared war on Japan on December 8, 1942. Based on the Axis Powers Agreement, Germany Declared war on the United States, and the United States responded immediately. (I think it is more accurate to say that the United States joined the Allied Powers in declaring war on Japan, and the Allied Powers declared war on the Axis Powers.)

2. Hitler hoped to use Japan to contain the United States, because the United States did not need materials from Britain or France. There is actually a lot of help from the military.

3. Hitler knew that if the United States did not participate in the war, the economy would be very strong after recovery, and he did not want to wait for the United States to reap the benefits.

4. The United States was home to a large number of Jewish immigrants and refugees around the world at that time. Sooner or later they would try their best to get the United States to declare war on Germany.