The fundamental question in mcculloch v. maryland involved the ability of the U.S. government to pass laws not listed in the U.S. Constitution!
McCulloch v. Maryland, 17 U.S. 316 (1819), was a decision by the U.S Supreme Court. The state of Maryland had attempted to halt operation of a branch of the Second Bank of the U.S. by imposing a tax on all money of banks not chartered in Maryland. The law applied to all banks not based in Maryland. This Second Bank was, in Maryland, was the only out-of-state bank then, so the law was specifically made for the Second Bank. Then Court created the "Necessary and Proper Clause" of the Constitution, which allowed the Federal government to pass laws not mentioned in the Constitution's powers. It was a go-around way from following the Constitution.