Germany
Japan forced the US into WWII by attacking Pearl Harbor, Hawaii.
Russia
World War 2 : Japan.
country B - apex
The bombing of Pearl Harbor by Japan pulled the U.S. into WWII
A harbor and navy base near Honolulu, Hawaii. It was the site of the surprise Japanese attack on the US that forced the US to enter world War 2.
We didn't, it was in the Fifth Century BCE, 2,200 years before us bacame an independent country.
Tension
There were many factors which moved the US toward hostilities in World War II, but the causus belli was the Japanese attack on the US fleet at Pearl Harbor on Dec 7th, 1941. The US immediately declared war on Japan, after which Germany (rather inexplicably) declared war on the US.
United States had to construct the country from the get go since Japan had no resources after the war.
I'm kinda sure they invaded Poland.