Which document served as the foundational framework for the U.S. government structure?

The Constitution of the United States serves as the foundational framework for the structure of the U.S. government. It was drafted in 1787 and established the three branches of government: legislative, executive, and judicial. This document outlines the powers of each branch, the system of checks and balances designed to prevent any one branch from becoming too powerful, and the federal structure that distributes power between the national and state governments. It also embodies the principles of democracy and the rule of law that are central to the United States' political system.

While the Articles of Confederation laid the groundwork for a national government after independence, they proved insufficient due to their weak central authority. The Declaration of Independence primarily addressed the colonies' separation from British rule, outlining the philosophical justification for independence rather than establishing a governing framework. The Bill of Rights, which consists of the first ten amendments to the Constitution, provides specific protections for individual liberties but is not the foundational document for the structure of government itself. Thus, the Constitution is correctly identified as the essential document that established the United States' governmental framework.