The clause establishes the Constitution, Federal Statutes, and U.S. treaties as "the supreme law of the land". The text establishes these as the highest form of law in the American legal system, mandating that state judges uphold them, even if state laws or constitutions conflict.
necessary and proper clause
The Congress shall have Power - To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof.
Dred Scott vs. Sanford
A decision by the United States Supreme Court that ruled that people of African descent imported into the United States and held as slaves, or their descendants—whether or not they were slaves—were not protected by the Constitution and could never be citizens of the United States.
Marbury vs. Madison
Landmark case in the U.S. Law, it formed the basis for the excercise of Judicial Review under Article III of the constitution
All men in 1818 are citizens, "Equal protection of the laws," and defines citizenship