Which principle of government prevents one branch from becoming too powerful?

Checks and balances is the principle designed to ensure that no single branch of government—executive, legislative, or judicial—can dominate the others. This system establishes a framework in which each branch has specific powers and responsibilities, as well as the ability to limit the powers of the other branches. For instance, the legislative branch makes laws, but the executive branch has the power to veto those laws, and the judicial branch can review laws to determine their constitutionality. This interdependence creates a system of oversight and prevents the concentration of power, reinforcing the democratic foundation of the government.

Federalism refers to the division of power between the national and state governments, which is important for understandings of governance but does not directly address the balance of power within the branches of government. Judicial review is the power of the courts to assess whether a law is in compliance with the Constitution, which is certainly a crucial element of maintaining balance, but is only one component of the broader system of checks and balances. Popular sovereignty addresses the idea that the authority of the government is created and sustained by the consent of its people, but it does not specifically relate to how the branches of government interact with and constrain one another.