The supposition that constitutionalists believe that the federal Constitution magically limits/inhibits government simply through words on parchment is nothing but a caricature and straw-man. Almost no one believes this, or argues in such a way.
All contracts, written constitutions or not, are only as good as the enforcement of their stipulations and the continuance of their principles. All of these things, of course, take civic virtue and a tireless, committed population of individuals who cherish liberty. Lacking these factors, all contracts read only as dead letters.
James Madison, Thomas Jefferson, St. George Tucker, and many others said the same.