The health-care legislation’s expansion of the federal government’s purview has improved our civic health by rekindling interest in what this expansion threatens — the Framers’ design for limited government. Conservatives distraught about the survival of the individual mandate are missing the considerable consolation prize they won when the Supreme Court rejected a constitutional rationale for the mandate — Congress’s rationale — that was pregnant with rampant statism. …

If the mandate had been upheld under the Commerce Clause, the Supreme Court would have decisively construed this clause so permissively as to give Congress an essentially unlimited police power — the power to mandate, proscribe and regulate behavior for whatever Congress deems a public benefit. Instead, the court rejected the Obama administration’s Commerce Clause doctrine. The court remains clearly committed to this previous holding: “Under our written Constitution . . . the limitation of congressional authority is not solely a matter of legislative grace.” …

By persuading the court to reject a Commerce Clause rationale for a president’s signature act, the conservative legal insurgency against Obamacare has won a huge victory for the long haul. This victory will help revive a venerable tradition of America’s political culture, that of viewing congressional actions with a skeptical constitutional squint, searching for congruence with the Constitution’s architecture of enumerated powers. By rejecting the Commerce Clause rationale, Thursday’s decision reaffirmed the Constitution’s foundational premise: Enumerated powers are necessarily limited because, as Chief Justice John Marshall said, “the enumeration presupposes something not enumerated.”