"Amendment X. The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or

"Amendment X. The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people." The Federal government should only exercise enumerated powers. Thomas Jefferson struggled with the Louisiana Purchase because buying land is not an enumerated power. Of course this document also has a Necessary and Proper Clause and an Interstate Commerce Clause. In practice judges on special courts decide if they value drug prohibition or the semi-sovereignty of states more.