The question, then, is not, How did the 10th Amendment limit the power of federal government? but rather, in what ways does it not?It’s tempting to say that the Bill of Rights and later Amendments specifically grant the federal government power. For example, it is tempting to say that the First Amendment gives the federal government the power to protect free speech. But it does not. The First Amendment specifically stops Congress from abridging on free speech, press, or religion, or creating an official religion. In general, the Bill of Rights limits federal action. State Constitutions, if they do not have similar restrictions, do not prevent state and local authorities or private actors from acting. While this is not always true, it is certainly true for the First Amendment. This was the case until the Fourteenth Amendment became incorporated. The Fourteenth Amendment guarantees equal protection under the law. The Court has interpreted this to mean that all elements of the Constitution must be equally enforced, as has federal law. To what degree this undermines the Tenth Amendment and obviates state constitutions is constantly debated.Do note, though, that the language is not so specific in all the Amendments, even without the Fourteenth Amendment. For example, the Fourth Amendment states The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized. That does not specify the states. Nor does the Third Amendment, which says, No Soldier shall, in time of peace be quartered in any house, without the consent of the Owner, nor in time of war, but in a manner to be prescribed by law. In fact, the only Amendment that mentions the Congress of the Bill of Rights is the First!