d. regulate commerce with foreign nations, and among the several states;
e. regulate immigration and bankruptcy;
f. establish post offices;
g. control the issuance of patents and copyrights;
h. declare war;
i. pass all laws needed to govern the District of Columbia and federal military enclaves (e.g., military bases); and
j. “make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States. … ” This is the so-called “necessary and proper” clause.
2. Other sources: Other parts of the Constitution provide additional grants of power to the various branches of the federal government. Article II defines the powers and duties of the President. Article III confers the federal judicial power (and also gives Congress power to control Supreme Court jurisdiction). Other grants of power are scattered throughout the document (e.g., Article IV, §3 gives Congress power over U.S. territories and federal property). Finally, many of the amendments specifically give Congress the power to enact supporting legislation (e.g., §5 of the Fourteenth Amendment). See N&R, p. 128.
3. Foreign affairs power: One exception has been recognized to the general rule that only enumerated powers may be exercised by the federal government. Nothing in the Constitution explicitly gives the federal government the power to regulate foreign affairs (though Article I, §8, gives Congress the right to “regulate Commerce with foreign Nations”). The federal government’s right to conduct foreign affairs is generally considered to be implied by the nature of the federal union, and by the impracticability of having each of the several states conduct its own foreign policy. N&R, pp. 133-34.
A. Doctrine of implied powers: Although the federal government may act only where it is affirmatively authorized to do so by the Constitution, the authorization does not have to be explicit. That is, by the doctrine of “implied powers,” the federal government (especially Congress) may validly exercise power that is ancillary to one of the powers explicitly listed in the Constitution, so long as this ancillary power does not conflict with specific constitutional prohibitions (e.g., those of the Bill of Rights). See Tribe, p. 301.