Roger Scruton in The City Journal:
Wherever the Western vision of political order has gained a foothold, we find freedom of expression: not merely the freedom to disagree with others publicly about matters of faith and morality but also the freedom to satirize solemnity and to ridicule nonsense, including solemnity and nonsense of the sacred kind. This freedom of conscience requires secular government. But what makes secular government legitimate?
That question is the starting point of Western political philosophy, the consensus among modern thinkers being that sovereignty and law are made legitimate by the consent of those who must obey them. They show this consent in two ways: by a real or implied “social contract,” whereby each person agrees with every other to the principles of government; and by a political process through which each person participates in the making and enacting of the law. The right and duty of participation is what we mean, or ought to mean, by “citizenship,” and the distinction between political and religious communities can be summed up in the view that political communities are composed of citizens and religious communities of subjects—of those who have “submitted.” If we want a simple definition of the West as it is today, the concept of citizenship is a good starting point. That is what millions of migrants are roaming the world in search of: an order that confers security and freedom in exchange for consent.
More here.