God has no interest in establishing a good government on earth, except through the triumphant return of Christ. That's why the New Testament ignores the problems of law and society outside the church.
Then why didn't God just leave us under King George? Our founding fathers certainly thought Providence was at hand. I think God desires for government to be good, just as he desires for man to be good. But the greater problem is man. Government is a reflection of man. If God could get all men to repent and follow him, government would be good.