United States Constitution

The Constitution of the United States is the agreement that formed the current United States of America. It replaced the Articles of Confederation. It was drafted in 1787 at the Philadelphia Convention, and entered into force with the ratification of New Hampshire on June 21, 1788.

Ratification
The Constitution stipulates that in order for it to enter into force, nine of the thirteen states had to approve it, as opposed to unanimous agreement required by the Articles of Confederation.

The ninth state to agree to the Constitution was New Hampshire, on June 21, 1788. Eventually, all thirteen states ratified, but three of them—Virginia, New York, and Rhode Island—did so by small majorities and included the stipulation that the state could at some time in the future revoke its ratification. Virginia's ratification document said: "The powers granted under the Constitution, being derived from the people of the United States, may be resumed by them, whensoever the same shall be perverted to their injury or oppression, and that every power not granted thereby remains with them, and at their will."

Interpretations
By the early 19th century, two schools of thought regarding interpretation of the Constitution had developed, commonly referred to as the "Nationalist" theory and the "Compact" theory.

Nationalist theory
The Nationalist theory argues that the Constitution formed a sovereign nation, under which the states are subordinate in power to the federal government. Thus, the powers of secession and nullification, according to the theory, are unconstitutional.

Prominent advocates of the Nationalist theory include Alexander Hamilton, John Marshall, Daniel Webster, and Abraham Lincoln.

Compact theory
The Compact theory argues that the Constitution was a compact, that is, the voluntary agreement of thirteen sovereign states to create a general government to take on specific roles. According to the theory, the compact was voluntary and the states retain their sovereignty, so any state has the right, under the Constitution, to secede from the Union. Some proponents of the Compact theory also argued that nullification, that is, a state's refusal to obey a law of the general government, was also constitutional.

Prominent advocates of the Compact theory include Thomas Jefferson, Abel P. Upshur, and Jefferson Davis.

Other interpretations
Lysander Spooner argued in his 1867 work No Treason that the Constitution is not a valid contract. As a result, no individual could be bound by it except those few individuals who actually signed the original document.

Amendments
Since its original ratification, the Constitution has been officially amended 27 times. The first 10 of these 27 amendments are collectively known as the Bill of Rights.