The Poles understand that the Russians were allied with the Germans to dismember Poland in 1939, even if Americans generally do *not* understand this.
And remember that Britain and France were trying to woo Russia, before Russian signed with Hitler. The reason? Britain and France said “no” to Russia getting half of Poland in return.
So true. You know what else a lot of Americans fail to understand? Around that same time Ukrainians were teaming up with the German Nazis to ethnically cleanse Ukraine of Jews and Russians. It is within the living memory of those people in the Donbas today. They suffered mightily from that alliance. And much of that history goes to the heart of what is going on in Eastern Ukraine now.
They also remember the Ukes ghastly Banderist OUN mass murders against Poles from the same time period.