a diplomatic treaty of non-aggression
It was not merely a non-aggression treaty; in fact, it also divided much of Eastern Europe into German and Soviet “spheres of influence” and set the stage for the Soviet invasions of Finland and eastern Poland a mere three months and less than a month after signing the treaty, respectively, with additional provisions for many more countries and regions. In short, aggression was very much part of the treaty, despite its name. As mentioned in the Wikipedia article on it:
[t]here was also a secret protocol to the pact, which was revealed only after Germany’s defeat in 1945 although hints about its provisions had been leaked much earlier, so as to influence Lithuania. According to the protocol, Poland, Romania, Lithuania, Latvia, Estonia, and Finland were divided into German and Soviet “spheres of influence”. In the north, Finland, Estonia, and Latvia were assigned to the Soviet sphere. Poland was to be partitioned in the event of its “political rearrangement”: the areas east of the Pisa, Narew, Vistula, and San rivers would go to the Soviet Union, and Germany would occupy the west. Lithuania, which was adjacent to East Prussia, was assigned to the German sphere of influence, but a second secret protocol, agreed to in September 1939, reassigned Lithuania to the Soviet Union. According to the protocol, Lithuania would be granted its historical capital, Vilnius, which was part of Poland during the interwar period. Another clause stipulated that Germany would not interfere with the Soviet Union’s actions towards Bessarabia, which was then part of Romania. As a result, Bessarabia as well as the Northern Bukovina and Hertsa regions were occupied by the Soviets and integrated into the Soviet Union.
You write that:
[…] tankies will consider it either ignorant or bad faith to bring up the Ribbentrop Pact to pretend it was anything more than realpolitik compromise resulting from the Western powers wanting the two countries to destroy each other.
First, it is not and was not at the time clear that the entire West wanted the Soviet Union and the Third Reich to wear each other out; instead, it was a Soviet belief, as you quote yourself:
The Soviet leadership believed that the West wanted to encourage German aggression in the East and to stay neutral in a war initiated by Germany in the hope that Germany and the Soviet Union would wear each other out and put an end to both regimes.
That belief was questionable. The fact is that the West allied with the Soviet Union and supported it, through Lend-Lease and other means, after it was betrayed by the Third Reich. Of course, hindsight is hindsight, and Soviet leadership did have reasons to believe the West wanted them to fight against the Third Reich, but their assessment was fatally flawed and led to much suffering, not least amongst their own citizenry.
Second, you ignore Soviet agency and deflect Soviet responsibility to the West when you describe the Molotov–Ribbentrop Pact as “realpolitik compromise resulting from the Western powers wanting the two countries to destroy each other”. That is akin to saying “look what you made me do”, edition “ally with Hitler”. The Molotov–Ribbentrop Pact did not “result” from anything; the Soviet Union conceived that treaty, including its infamous Secret Protocol, as much as the Third Reich did.
Finally, you write that:
tankies will probably disagree when someone claims the country that invaded the USSR was a ‘friend’ […]
and that:
[…] the USSR didn’t want to be friends with […]
Strictly speaking, states cannot be friends; only people. Therefore, the comments by @PrincessLeiasCat@sh.itjust.works and @seejur@lemmy.world must be understood figuratively.
Figuratively, the Soviet Union and the Third Reich may be described to have been “friends” up until the Nazi betrayal in 1941. After all, the Soviet Union agreed to a treaty that benefited the Third Reich. In fact, even the non-aggression part of the Molotov–Ribbentrop Pact benefited the Third Reich, because it freed up German resources and enabled the Western Blitz. It could be argued that Soviet leadership intended to let the Third Reich and the West wear each other out.
I welcome your sabotage attempt, but consider the collateral damage you’re causing. I sprained a few neurons reading your comment.