It didn't always require government. All it required was people who understood civic virtue and weren't afraid to practice it.
Just to help you understand this, every high school has a dress code. Most high schools don't have an administrative policy on dress codes, but those high schools have them just the same. The administration doesn't enforce them.
The students do.
Shalom.
It never required government. And when Americans started allowing government to decide for them, the standards always fell.