George Will, Mike Huckabee and the Two Kingdoms
The Kingdom of the Left hand- the realm of law and coercion and power (not limited to the State, btw; equally present in church government) is as much God's kingdom to govern as the Kingdom of the Right- the kingdom of grace and the Gospel. But the Kingdom of the Left includes all of God's human creatures- including unbelievers. Its currency isn't the Gospel. It's reason and justice- the common currency of just and reasonable men whether they're believers or not.
Yes, we Christians would argue that, in substance, that's nothing other than the Law. But it's the Law as written on the human heart, and not simply as written in the Scriptures.
HT: Real Clear Politics