I read about risk of communist influence, hundreds or tens of thousands dead over those 21 years due to US involvement etc, but what was a realistic alternative to what the US and the countries did?
If no one did anything wouldn't the communists eventually do coups with the USSR's blessing and eventually nuclear weapons would be brought in like in Cuba, giving the USSR's nukes extremely short flight time to key US cities? Doesn't exactly seem to be in anyone's interest.
Sorry, but your submission has been removed because we don't allow hypothetical questions. If possible, please feel free to rephrase the question so that it does not call for such speculation, and resubmit. Otherwise, this sort of thing is better suited for /r/HistoryWhatIf or /r/HistoricalWhatIf. You can find a more in-depth discussion of this rule here.