While almost all forms of communism are atheistic, not every form of atheism is communistic. Some are anticommunist, as a matter of fact. Inverting this relationship is a logical fallacy.
I agree...indeed, and with the exception of monastic communities (where property is willingly surrendered and redistributed) communism is an abject failure where property is ultimately surrendered and redistributed by force.
I will take CS Lewis's tact in regards to your second assertion, and that is simply, that I don't believe in atheists. People will invent a god of their own making, if indeed, it is something as ridiculous as embracing atheism as their religion. My point is, our founders cemented our republic in the belief of a GOD...not necessarily a Christian God, but certainly a supreme force that exists above, and transcends the human experience. This is irrefutable, and a reading of the Declaration of Independence makes this lucidly clear to any but the most obtuse among us...