Your understanding of pretty much every single point you made is entirely ahistorical and inconsistent with actual records. However, it's 100% consistent with Western liberal propaganda including schooling.
The Molotov-Ribbentrop agreement was made, according to historical record, to give the USSR a better chance at surviving the coming onslaught. There were no illusions on Stalin's part that the war was coming for the USSR as Hitler literally announced his intentions in Mein Kampf.
The idea that the USSR invaded Poland is a Western narrative reframing of the conflict between the USSR and the Third Reich.
The idea that allied supply lines are equivalent to millions of Soviet deaths is divorced from reality.
The idea that Stalin engaged in a land grab is equally a Western narrative reframing the post-war reality. The USSR marched all the way to Berlin. Every country they marched through had been destroyed by the war. The options were to leave them for the anti-communist to come through and attempt to destroy the USSR or stay behind and build self-governing Soviet republics. Unlike the land grabs of Japan, Germany, England, France, Spain, Portugal, the Netherlands, and the USA, the USSR built democratic republics and gave them the right to secede from the union. The majority of people in the former republics have said, through polls, that dismantling the USSR did more harm to them than good.
In the years immediately following the war the USA built NATO, staffed it with Nazis, executed Operation Paperclip to distribute Nazis all over the Western hemisphere, and executed Operation Gladio to arm, train, fund, and organize fascist militias all over Europe so that if the USSR ever backed out of any place it would immediately be taken over by fascists. Then the USA went on a massive killing spree all over the world.
As for your incorrect understanding of the Japanese surrender, you need to actually read the historical record. The USA and Britain disagreed on the terms and the USA insisted in strongarming the negotiations. The Soviets were trying to negotiate with Japan, but the USA wanted the Soviets out of the Pacific. The Japanese were in active negotiations and after several back-and-forths the USA made the Potsdam Declaration. The Japanese, imagining they were negotiating with rational human beings, rejected the terms and asked for specific conditions about maintaining their social institutions around the monarchy. The USA nuked hundreds of thousands of civilians in response.
There is absolutely no evidence to suggest that it saved lives. Your entire framing is that the USA was allowed to just decide to do whatever it wanted because it won, up to and including nukes on civilians. This position is psychopathic.
Governments were shit back then
Mother fucker it was only 80 years ago. Are you that fucking daft? The USA got WORSE in those 80 years, not better.
Comparing Wagner group to the Mujahideen is ridiculous. Just pure brain rot.
As for this ridiculous idea that governments are better now... Isn't it curious that it happened after you were born? Almost like now that you're here, things are better. Of course they'd have to be, otherwise you would be living in an evil empire. And you aren't are you? That would be terrible.
The reality is that the CIA still operates black sites where they torture people, the supreme Court protects them, the Congress protects them, the executive branch protects them. The US has invaded more countries after WW2 than before. In Libya, the country with the highest standard of living in all of Africa, the US bombed it to oblivion. After the president was lynched in the streets, Hillary Clinton, paragon of governments not being shits anymore, said "We came. We saw. He died."
The amount of violent oppression the USA has delivered around the world since the end of world war 2 is unfathomable. The School of the Americas, alone, is responsible for so much bloodletting, and that's just a fucking school.
Your entire world view is a collection of false narratives created by North Atlantic propagandists based on cherry picked facts that give them the veneer of authenticity. The reality is that the USA is the inheritor and current head of the 6 century North Atlantic project of global domination and nothing is off the table for them: nuking civilians, genocide, species extinction, child trafficking, systematized torture, overt military occupation, assassination, coups of democratically elected governments, medical experiments, apartheid, ghettoization, mass incarceration, slave labor.
Just because you're here now doesn't mean that suddenly governments are more rational.