Japan
Russia.
Japan & Germany .
They were mainly Germany , Italy and Japan.
During World War 2, California was part of the United States, so any enemy of the U.S. would, by extension, have been an enemy of California. For example, Italy, Japan, or Germany.
The most obvious answer to this question would be; The Martians. It is argued that they are the enemy since they invaded planet Earth.
china and japan
The British
They can be obtained from any enemy in any war and usually are used as an item to exchange for weapons/armour.
During WW2, Germany, Italy, Romania, Hungary, Japan, and all other Axis coutnries were his enemies. After WW2 during the Cold War, the US was their enemy.
It was the enemy capital. Traditionally, most countries crumble whenever their capital falls under enemy control.
Germany.