What document outlines the foundational laws and principles of the United States government?

The Constitution of the United States is the foundational document that establishes the framework and core principles of the American government. Ratified in 1788, it outlines the structure of the federal government, delineates the powers and responsibilities of its three branches—legislative, executive, and judicial—and includes the mechanisms for checks and balances to prevent any one branch from becoming too powerful. Additionally, the Constitution enumerates the rights of the citizens through its amendments, ultimately providing a comprehensive legal foundation for governance in the nation.

While the Articles of Confederation were the first attempt at a governing document for the United States, they proved inadequate due to their inability to create a strong central authority. The Bill of Rights, which comprises the first ten amendments to the Constitution, serves to protect individual liberties but is not a stand-alone document that establishes government structure. The Declaration of Independence expresses the colonies' reasons for seeking independence and outlines certain philosophical ideas about government but does not create the governing laws themselves. Thus, the Constitution is the correct answer as it serves as the bedrock of U.S. law and governance.