Answer:
1. Slavery: Debates over the constitutionality of slavery have been a major part of American history, with opponents arguing that the document's guarantee of equal protection under the law does not extend to those in bondage. Supporters of slavery have argued that the Constitution's framers did not intend to end the practice, and that it is a state right.
2. Separation of Powers: This debate centers around the interpretation of the separation of powers outlined in the Constitution. Supporters of a strict interpretation argue that the executive, legislative, and judicial branches must remain separate, while opponents argue for a more flexible interpretation that allows for collaboration between the branches.
3. Federalism: This debate centers on the nature of the federal government's relationship with the states. Supporters of a strong central government argue that the Constitution grants it broad powers over the states, while opponents argue for more limited powers for the federal government, and a greater degree of autonomy for the states.