There is no such thing. You can disbelieve, but that's still a religion. And belief or lack of belief doesnt change the fact that God is still there.
And yes, for most of history church and state went hand and hand. Thankfully, the Founders learned from early Israel and the early Christian ages when there wasnt a Church and state established.
That's kind of funny from someone who belongs to the only "religion" who attempted to establish a theocracy in this country before the feds slapped you down in 1857.
And if Atheism is a religion, then not collecting stamps is a hobby.
By your own standards, you have a lot of religions then.
You don't believe in Baal, Zeus, Odin, Osiris, Krishna, Amaterasu, etc. There a whole lot of Gods you don't believe in, therefore you have a lot of religions.
I just believe in one less God than you do.