What is the supreme law of the land?

The Constitution is the supreme law of the United States. Adopted in 1787 and ratified in 1788, it establishes the structure of the federal government, defines the rights and duties of citizens, and sets the relationship between the states and the federal government. The Supremacy Clause in Article VI states that the Constitution and federal laws made under it are 'the supreme law of the land,' meaning state laws cannot conflict with federal law on matters where the federal government has authority. The Bill of Rights consists of the first ten amendments to the Constitution; it is part of the Constitution, not separate from it. The Declaration of Independence (1776) is a foundational historical document but is not law. Federal statutes are valid only when they do not conflict with the Constitution.