Yes, absolute power corrupts absolutely. This is the root of Communism. And it is wrong.
But to club Communism with Atheism, and mix arguments, will convince none.
Selfishness is recognised in all religions, by the way, since the dawn of time.
Even a thinking atheist should see communism goes against human nature.
The problem is they are deceived in a lot of things, not just victims of a single mistake.