How does this author think that Stalinist practices came to be used in The Soviet Union? They certainly weren't baked into the Soviet Constitution (Yes, they had one, and according to Alexander Solzhenitsyn, it was a very good one too)
They came to use Stalinist methods because they were allowed to, and nobody stopped them. While their Constitution was paper and nothing more (because it was never intended to be followed, it was intended to be interpreted and defined as the state saw fit to suit its needs) our Constitution is suffering the same fate even if the origins of the document were more honest.
And if we don't stop Leftist judges from twisting the Constitution to suit their needs, and we continue to allow local, state, and federal institutions and politicians to ignore what they want with no penalty, we are going to go down that road too.
How does this author think that Stalinist practices came to be used in The Soviet Union?
I think Cohen means that the commies in American haven't (yet) killed millions of people as was done in Stalinist Russia.