Which principle is NOT part of the Constitution?

The principle that is not part of the Constitution is monarchy. The U.S. Constitution establishes a democratic framework for governance, founded on the idea of a republic rather than a monarchy. In a monarchy, a single ruler (king or queen) holds significant power, often hereditary in nature, which is contrary to the democratic principles outlined in the Constitution.

In contrast, popular sovereignty, separation of powers, and checks and balances are fundamental principles embedded in the Constitution. Popular sovereignty emphasizes that the authority of government is derived from the consent of the governed. Separation of powers divides government responsibilities into distinct branches to limit any one branch from exercising the core functions of another. Checks and balances ensure that the different branches of government can regulate each other's powers, preventing any one branch from becoming too dominant. These principles are central to the effective functioning of the U.S. government and underscore its commitment to a system that protects democratic governance.