Supranational constitutionalism refers to the application of constitutionalism (normally associated with states), or constitutionalist thinking, to the realm of a supranational polity. Applying constitutionalism to supranational or international organizations is controversial, since it erodes the idea of the nation-state, although not unfamiliar in the case of the European Union (EU). Constitutions in the classic liberal sense established polities, defined who the people subject to them were, and created regimes including institutions and decision-making procedures. Crucially, they limited the scope of governmental intervention by establishing the principles of division of powers, submission to the rule of law, and human rights protection.