Not to defend Stalin but, those 26 million died during WWII. 8 million in the fighting alone, another 3 million in POW camps. It's a bit of a stretch to say Stalin murdered people who in fact died of starvation sitting in German occupied territory. And rather creative to imagine they would have died anyway, Nazi invasion or not.

Compare to the Taiping Rebellion, in which roughly 20-70 million died in a religious war. The Cato institute chooses not cite this as proof that religion is more violent than Nazi carnage. I suppose because both claims are equally ridiculous but only one matches Cato's coldwar ideology.