"We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America."
Explicitly stating that we are giving the government this Constitution so that it understands its duties and limitations of authority over the sovereign individuals (We the People) and the sovereign States. There are many laws that have been passed by Congress that are beyond Constitutional limits, and yet instead of performing its own Constitutional mandate, the Supreme Court often interprets the Constitution in phrases, which removes from its substance the original intent. At that point most Americans throw up their hands in surrender to "the powers that be" and resign to the fact that "the law is the law," and we just have to obey it.
But those very smart founders left a remedy that is seldom used today when testing an act of Congress for Constitutional integrity. The States have the power, the responsibility and duty to nullify laws that violate the U.S. Constitution as well as their State's. In those places like California and Oregon where the People can petition and get an initiate or measure on the ballot, they can vote to overturn laws that violate their rights as Sovereigns within their respective States.