The significance of the U.S. Constitution lies in its establishment of a framework for governance that embodies the principles of democracy, federalism, and the rule of law. Ratified in 1788, the Constitution created a separation of powers among the legislative, executive, and judicial branches, ensuring checks and balances that prevent any single entity from gaining too much authority. It enshrined fundamental rights through the Bill of Rights, shaping American identity and political culture. The Constitution has proven adaptable and resilient, providing a stable governance structure while allowing for amendments in response to changing societal values.