They were never bogged down in Poland only a few decisions were used , the bulk of the army bypassed french defences by attacking through Belgium.
UK sent such forces as they had to France but were overrun and defeated at Dunkirk where they lost all their equipment. What was left of the french army capitulated.
The German army dominated all of Europe except Spain under Franco and Switzerland.
The effective, fight back only started on the ground when Germany made the mistake of invading Russia.
Well, the point I was making, in light of your criticism of the US joining the war late, was that both Britain and France were also slow to act against Germany, even despite declaring war. That's why many called it the "Phony War."
It wasn't because the Allies didn't have a strong enough force to repel the Germans, but they were outmaneuvered. That's more a reflection on the top leadership, not the soldiers in the field.
But yes, once the Germans invaded Russia, that was a fatal mistake which would eventually spell their doom. Some might also point to Germany's declaration of war on the United States as another fatal blunder, especially since Japan did not declare war on the USSR.
The main problem for Germany was that they had very little oil. That was the main reason for their impetuous move into Russia, as they were desperate for oil. The U.S. was practically swimming in oil, so we didn't have that problem.
