Stalin was working with Hitler even before Munich. The USSR helped the Germans test and develop tanks and aircraft during the interwar period as well as working with Hitler to carve up Poland and seize the Baltic States and other chunks of territory.
The USSR was still sending trains full of aid to the Nazis pretty much up to the minute that Barbarossa kicked off.
Are you denying that the USSR lost millions upon millions of men on the Eastern Front?
Until 1933, Germany was a completely democratic country (even Hitler came to power democratically).Pre-Hitler Germany and the USSR were both "pariahs" for other capitalist countries. Therefore, the Soviet Union, experiencing hostile pressure, allowed the germans (democratic germans, let me remind you) to open two schools in Russia, where the Germans trained tankmen and pilots. The Soviet military used these schools to train its specialists, as Germany was more advanced in both aircraft and tank construction. After Hitler came to power, these contacts were immediately terminated.
The USSR was the only country in the 30s that actually fought the Nazis, for example in Spain. All time in 30s USSR tried to create a system of collective security against Hitler. Through the fault of appeasers in England and France, it failed. It turned out that these politicians wanted Hitler to go east. So, Hitler proposed a non-aggression Pact, and the USSR accepted it thus receiving a reprieve from the war of almost two years. Very important years. after all, the USSR began to create a mass army only in 1939. By the way, this led to the fact that in 1941 the officers were not sufficiently trained. there were not enough experienced officers for the entire multi-million-strong army .
Alas, the USSR could not afford to create a powerful industry and maintain a million-strong army in the 30s. The USSR still hoped to rein in Hitler. Future allies prevented this. Yes, the USSR supplied food to Hitler, but this was not a one-sided process. In response, the USSR received modern machine tools from Germany, which, by the way, then created weapons for the war with Germany all through the war, samples of new german military equipment (Hitler allowed this to be done, being sure that the untermensch would not have time to use them) and other goods necessary for Soviet industry.
On the web, you can find a list of valuable goods the USSR received from Germany for a year and a half. In any case, the work of historians in the russian language.
Yes, there were heavy losses. The whole Europe, united by Hitler, the whole f***ng EU #1. with all its power and human resources, motivated to plunder by its theory of superiority, descended on the USSR. Fortunately for all mankind, the USSR was a country of socialism, capable of defending itself and crushing nazism.
You are welcome.