Pacifier

That is a too big "what if" to get a somewhat realistic answer.

nope, no superpower or "empire" survies that long

depends if there was a WW2 at all. Without the US the WW1 may have ended earlier with a "fairer" treaty thus perhaps not resulting in Hitler.

Churchill claimed that the US prolonged the War because the Allies felt more triumphant and aimed for germanys complete surrende. Without US both nation would have reached a status were war was no longer possible.

America should have minded her own business and stayed out of the World War. If you hadn't entered the war the Allies would have made peace with Germany in the Spring of 1917. Had we made peace then there would have been no collapse in Russia followed by Communism, no breakdown in Italy followed by Fascism, and Germany would not have signed the Versailles Treaty, which has enthroned Nazism in Germany. If America had stayed out of the war, all these isms wouldn't today be sweeping the continent of Europe and breaking down parliamentary government— and if England had made peace early in 1917, it would have saved over one million British, French, American, and other lives. [purportedly, interview in New York Enquirer 1936]

To follow this thought, the war could have ended in a massive soldiers (french soldiers were revoltnig in 1917; germans sailors revoltet 1918) and peoples revolt against their goverments resulting in a couple of "peoples republics" over europe (could be good, but could also be very bad)

sounds far fetched? yep, this is "what if" after all

Unlikely, without a great enemy the SU would have been fallen apart much earlier, or perhaps evolved in a nore nice goverment since the outside pressure would no be there. This pressure resulted in the russians desire to compete and that demanded a totalitarian regime.

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"It seems to me that the idea of a personal God is an anthropological concept which I cannot take seriously. I also cannot imagine some will or goal outside the human sphere. Science has been charged with undermining morality, but the charge is unjust. A man's ethical behavior should be based effectually on sympathy, education, and social ties and needs; no religious basis is necessary. Man would indeed be in a poor way if he had to be restrained by fear of punishment and hope of reward after death
— Albert Einstein