[Borges]

I would say that Stalinsm, Nazism and Maoism were religions in the sense that there was an orthodoxy and those who didn't follow it were dealt with harshly. The difference is that they didn't have any theology as oppososed to theocratic dictatorships like Calvin's Geneva and Cromwell's England.

[AmishDude]

Moreover, Marxism, etc. are philosophies based very much on faith. The world was simply going to happen the way Marx predicted, despite evidence to the contrary.

[ReignOfError]

I would say that Stalinsm, Nazism and Maoism were religions in the sense that there was an orthodoxy and those who didn't follow it were dealt with harshly. The difference is that they didn't have any theology as oppososed to theocratic dictatorships like Calvin's Geneva and Cromwell's England.

Bingo. Or, the way I put it is that religion per se isn't the problem -- dogma is. Any belief system that is oblivious to facts, crushes dissent and debate, and considers its people as means to an end fits the definition, whether it claims a supernatural justification or not.