Today, courts and commentators generally agree that early efforts to strictly limit the federal government to only expressly enumerated powers were decisively rebuffed by Chief Justice John Marshall in McCulloch v. Maryland. According to Marshall, the fact that the Framers departed from the language of the Articles of Confederation and omitted the term “expressly” suggested that they intended Congress to have a broad array of implied as well as expressly delegated powers. As Supreme Court Justice Joseph Story later wrote, any attempt to read the Tenth Amendment as calling for strict construction of federal power was simply an attempt to insert “expressly” into the text. Today, Marshall's point regarding the significance of this omitted term is probably one of the least controversial claims about the original understanding of Tenth Amendment as currently exists in legal commentary.
It is also almost certainly wrong. James Madison, Alexander Hamilton, early Supreme Court Justice Samuel Chase and numerous other members of the Founding generation regularly inserted into their description of federal power the very word that Marshall insisted had been intentionally left out. According to these Founders, Congress had only expressly delegated power. Upon investigation, it turns out that this rephrasing of the Tenth Amendment actually reflects the original understanding of the text and its underlying principle. Completely missed by generations of Tenth Amendment scholars, the addition of the phrase “or to the people” to the Tenth Amendment ensured that the Clause would be read as a declaration of popular sovereignty. According to this theory of government, the sovereign people were presumed to retain all powers not expressly delegated away. Repeatedly stressed by advocates of the Constitution as representing the proper construction of federal power, the principle of “expressly delegated powers” meant that Congress could utilize no other means except those necessarily or clearly incident to its enumerated responsibilities. Consistently read in combination with the Ninth Amendment's declaration of the retained rights of the people, the Tenth Amendment was broadly understand to establish a rule of strict construction of federal power - the very interpretive principle rejected by John Marshall in McCulloch v. Maryland.