If Russia were located beyond the ocean, she would not be bled by WWI and the small political sect of Bolsheviks could not seize power there.
Communism came from Western Europe and had broader support in Germany, Spain, France, Italy etc ... There was a bloody civil war in Spain, in Germany and Italy the Communism was suppressed by Fascism which in National Socialist form was not better than the Soviet system.
The core patriotic part of Russian society fought long war against the Reds (not so differently than it was done in Spain). They lost because they did not get help from abroad. The large part of the Soviet elite was recruited from non-Russians and the Soviet system mellowed over generations as Russian ethnic and cultural element took over for demographic reason.
the absence of such re-birth in the US means that the slavery here existed as sociologically superficial [with regard to the basis of civilization] phenomenon.
We do not know it. Slavery was integral part of culture and economy in the South and blacks got full civil rights only in the second half of XX century. Now we see the rise of Political Correctness and of totalitarian militant secularism (not so different from the one which devastated Russia.)
Do not take liberties for granted, and do not project weak aspects of the human nature which are UNIVERSAL into one demonized group be they Russian, Jews or Serbs. As history teaches, it brings evil fruits.