It's pretty basic rules that America as well as any society has had throughout history.
Don't lie
Don't cheat
Don't Steal
Don't murder
You don't have to believe in God to keep these basic rules.
When a larger majority of any society starts to violate the above, you have chaos and then government has to take over.
This is why full communist countries like North Korea and the U.S.S.R. has no religion because they became society's controller.
This is what our Founders was always talking about to have freedom you have to have morals.
If you notice, collectivists today, outside of Islam, tend to be atheists. This is no coincidence.
I think deep down we all desire a king to rule over us, it's just natural. You then either pick God or man to fill the role.
What many find strange is the alliance collectivists have with Islam. Islam believes in God and they are collectivists. However, those leaders in Islam purport to speak for God.
Looking at the recorded human history in terms of collectivists, man first claimed to be a god, and when that no longer worked he then he claimed to speak for God, and when that no longer worked he claimed that God did not exist, thus making himself the ultimate authority. I presume when the later has run its course we will revert back to people speaking for God, which is why I think Islam is the up and coming new world religion.