Because they conquered almost all of Europe, Japan threatened Asia, Australia, and The US. Hitler was a tyrant and was focused on world domination. The Germans had invaded important allies to Britain and the US such as France
The two main reasons for the Allies' victory over Axis powers in Europe were:
The entrance of the United States into the battle: Japan forced the United States into conflict with the outbreak of the surprise attack on the American base at Pearl Harbor in 1941. The following year, US and Japanese troops clashed at the Battle of Midway. In this confrontation the US victory took an important step to curb the advance of Japanese imperialism over various regions of the Pacific Ocean.
Tehran Conference
: In 1943, the allies held the Tehran Conference. At the conference, Russian President Joseph Stalin, US President Roosevelt and British Prime Minister Winston Churchill drew up a plan to end German power. According to the established points, the Allies planned the process of occupation of Western Europe. On June 6, 1944, known as Day "D", Commander Dwight D. Eisenhower captained the landing of 36 divisions, 6,400 ships and thousands of aircraft in the French region of Normandy. Undergoing an almost unshakeable offensive, the troops left the German armies completely crumpled. While these troops realized the dominion of Western Europe, the Russian troops recovered the territories of Eastern Europe. In the year 1945, the two fronts of battle converged towards the German territory. The city of Berlin was taken by the Soviets on May 1. The following week, the Nazi troops surrendered.
