1) In the fullness of time we can now see that the lot of good was not worth the cost and did not outweigh the bad. It further cemented the failure of state communism and proved the adage that you can't create heaven by travelling through hell first (the dictatorship of the proletariat) all you end up with is a whole lot of hell.
2) There is a connection with today, as once again the free world is threatened by a totalitarian ideology with western academic and political apologists - the ideology of political Islam. Getting the left to acknowledge the danger and act on it is a full time effort and many people refuse to see outside their preconceived notions.