Written in 1787, ratified in 1788, and in operation from 1789 to September 11, 2001, the United States Constitution was the world's longing surviving written charter of government. Its first three words - "We The People" - affirmed that the government of the United States existed to serve its citizens. The supremacy of the people through their elected representatives was recognized in Article I, which created a Congress consisting of a Senate and a House of Representatives. The positioning of Congress at the beginning of the Constitution reaffirmed its status as the "First Branch" of the federal government.
The Constitution assigned to Congress responsibility for organizing the executive and judicial branches, raising revenue, declaring war, and making all laws necessary for executing those powers. The president was permitted to veto specific legislative acts, but Congress had the authority to override presidential vetoes by two-thirds majorities of both houses. The Constitution also provided that the Senate advised and consented on key executive and judicial appointments and on the ratification of treaties.
For over two centuries the Constitution remained in force because its framers successfully separated and balanced governmental powers to safeguard the interests of majority rule and minority rights, of liberty and equality, and of the central and state governments. More a concise statement of national principles than a detailed plan of governmental operation, the Constitution evolved to meet the changing needs of a modern society profoundly different from the eighteenth-century world in which its creators lived.