Why did the allies declare war on Germany for invading Poland, but not the Soviet Union?

"The Molotov-Ribbentrop Pact divided Poland and other nations between them. They both attacked. Why did england and France only declare war on Germany?"

Best Answer - Chosen by Voters

Germany was the bigger threat, also the USSR did the allies a huge favor by taking Eastern Poland before the Germans could. It delayed Germany getting access to huge stockpiles of oil and created a buffer for the Soviets home territory. Stalin was a vicious killer, but he was not stupid. He knew the Germans were coming.

Because foreign policy is shaped in the vast majority by perceived national interest, not morality. No one cared about Poland's freedom - during the Soviet Union's occupation they murdered 10,000 Polish officers and members of the Polish intelligentsia (and buried them in mass graves in the Katyn Forest) in an attempt to decapitate the nation and it's capacity for resistence and dissent.

There is a purely formal reason.... both Franco-Polish Kasprzycki-Gamelin Convention and Polish-British Common Defence Pact obliged signing countries to provide military help to each other in case of a war with Nazi Germany. Soviet Union at the time of preparation of these documents was not considered to be a German ally.

Also, it allowed for the future allied pact which included the Soviet Union. hitler was the main threat at the time. didn't Stalin say that they were just "protecting" the Belorussians, who were, after all, the majority in the Russian sector of occupied Poland? Ah yes....politics and politicians don't always act logically....sorry.

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