Why didn't Stalin get any form of punishment for killing millions of his own people??

My counter question is "Who 'd punish him?".

None of his people would do that - take it from me.

Gulag archipelago was a ten thousand times the size of Guantanamo base, but was doing the same job "punishing the bad people, enemies of the Society" as any America would say.

But there is a difference apart from the War where his Red army was supposed to kill "enemy" soldiers; Stalin killed all his own countrymen, none of other nationals ¬ any Americans.

Further, Soviet Union paid the heaviest price in all terms more than all other countries put together (except perhaps, China in terms of human lives lost). Largest number of civilian dead & maimed were from that country & many who fought like soldiers. This "Collateral" loss is put at the door of Stalin, BECAUSE he was one man responsible for everything in USSR and who never ducked or shirked from this responsibility. There was no Congress, Senate to share decision making & power. I think, it is better that one man take all decisions when at a war that threatens its very existence.

Because he was part of the allies, his crimes before the start of WW2 were pretty much ignored. It would be no different if Germany was part of the allies. All in All our country has made many bad decisions in the past. We realize siding with the Soviet Union during WW2 wasn't exactly the best decision we made.

Who had the power to punish him? The only way to punish Stalin was either for him to be overthrown from within (and his underlings were just as guilty of crimes as he was), or from without (and no one was going to start a war with the USSR).

Stalin was in charge of the Politburo as well as the country, rather than the Politburo being in control of Stalin.

he was a dictator, who was going to punish him? His people were not willing to rise against him, and he isn't going to punish himself sooooo he got away with it.