An answer for strategists

Dear strategist, I invite you to reflect:

On which of the following dates do you believe Nazi Germany began to lose the war?

• September 1, 1939, when through “Operation White Case,” the invasion of Poland began, leading two days later, on September 3, to England and France declaring war on Germany.

• June 22, 1941, when Hitler launched “Operation Barbarossa” to invade the Soviet Union, conceived as a blitzkrieg operation.

• December 7, 1941, when Japan attacked the Pearl Harbor naval base in the Pacific, causing Germany to declare war on the United States on December 11, 1941.

Do not seek the answer from any historian or encyclopedia; apply your strategic thinking, and you will find the only correct answer.