CHARLOTTESVILLE, Va.

BOTH liberals and conservatives have the American Constitution in the cross hairs. They assault the Constitution in their different ways, each with damaging effects on our nation. Conservatives attack the courts on one hand and seek to have them advance their activist agenda on the other. Liberals, when it suits them, embrace rights that have not been enumerated in the Constitution and cry for restraint only when their pet bills come under fire. The result is a national jurisprudence whetted by political appetite, with our democratic values as the victims.

Conservatives increasingly bemoan Congress’s power to regulate interstate commerce, as illustrated by the debate over the Affordable Care Act’s requirement that individuals buy health insurance. They argue that Congress can only regulate activity, not inactivity, and so when it gets involved in a decision by a consumer to not purchase health care, it is going far beyond its reach.

If only it were that simple.

As a political argument, that resonates: “Don’t Tread On Me” trumpets the imperishable spirit of American liberty. But as a constitutional argument, it would imbue judges with unprecedented powers to topple an exhaustively debated and duly enacted federal law and to make the determination that the decision not to buy ice cream can be neatly severed from the decision to buy chocolate or vanilla.

In curbing federal excess, courts risk lessening our national economic strength. That strength resides partly in the national aspects of our founding document, among them the now maligned commerce clause and the newly mistrusted supremacy clause, which gives preference to federal over state law when there is a conflict. States’ rights are important in many spheres, but the benefits of a national economic policy must also be considered. A vibrant economic order requires some political predictability, and the prospect of judges’ striking down commercial regulation on ill-defined and subjective bases is a prescription for economic chaos that the framers, in a simpler time, had the good sense to head off.