Sally Kohn: There's much in American practice that runs against liberal theory. She says the idea that the state should preserve one day for rest for contemplation for prayer, etc., dates back to colonial era and stayed with U.S. after Revolution. In pure liberal theory, not delivering mail on Sunday would be a crime, she says; but it was allowed by Chamber of Commerce Republicans over many years until Jeff Bezos managed to convince postal service to have USPS drivers deliver Amazon products on Sunday.