What is the importance of mccullough v. maryland? ?

In a unanimous decision, the Court held that Congress had the power to incorporate the bank and that Maryland could not tax instruments of the national government employed in the execution of constitutional powers. Writing for the Court, Chief Justice Marshall noted that Congress possessed unenumerated powers not explicitly outlined in the Constitution. Marshall also held that while the states retained the power of taxation, "the Constitution and the laws made in pursuance thereof are supreme. . .they control the Constitution and laws of the respective states, and cannot be controlled by them."