in United States v. Butler. There, the Court agreed with Justice Story's construction, holding the power to tax and spend is an independent power; that is, the General Welfare Clause gives Congress power it might not derive anywhere else. However, the Court did limit the power to spending for matters affecting only the national welfare. The Court wrote:
[T]he [General Welfare] clause confers a power separate and distinct from those later enumerated, is not restricted in meaning by the grant of them, and Congress consequently has a substantive power to tax and to appropriate, limited only by the requirement that it shall be exercised to provide for the general welfare of the United States.
It results that the power of Congress to authorize expenditure of public moneys for public purposes is not limited by the direct grants of legislative power found in the Constitution.
But the adoption of the broader construction leaves the power to spend subject to limitations.
[T]he powers of taxation and appropriation extend only to matters of national, as distinguished from local, welfare.
The tax imposed in Butler was nevertheless held unconstitutional as a violation of the Tenth Amendment reservation of power to the states.
Shortly after Butler, in Helvering v. Davis,[22] the Supreme Court interpreted the clause even more expansively, conferring upon Congress a plenary power to impose taxes and to spend money for the general welfare subject almost entirely to its own discretion. Even more recently, the Court has included the power to indirectly coerce the states into adopting national standards by threatening to withhold federal funds in South Dakota v. Dole.[15]