Pensacola-based Judge Roger Vinson’s decision to invalidate the Affordable Care Act has been met with predictable derision on the left as “activism” and “driven…by ideology.” While not undeserved, such epithets do a disservice to progressives who both oppose Vinson’s decision and support causes such as abortion rights, same-sex marriage and civil liberties.

The core problem with Vinson’s opinion is not that it is “activism” or that it is “political.” The core problem is that it’s wrong. Making that case—the case for the healthcare law on the merits—is where progressive energies should be channeled. Judge Vinson’s decision does half the heavy lifting here. Its elaborate contortions of law, history and fact illustrate how hard it is to make a legally plausible, or ethically palatable, case against the individual mandate.

Most critics of the decision thus far have made one of two arguments: either they have opposed Vinson’s superfluous invocation of colonial protests against import taxes—a hat tip to the current tea party—or attacked his decision to leap from the putative unconstitutionality of the mandate to finding the whole law invalid.

Both are fair criticisms. The history of the colonial tea party is irrelevant to the legal question at hand. And on the question of whether the whole act should be invalidated, it is right to criticize Vinson for reading from the Congressional Republican playbook.

But both arguments miss a deeper point. In arguing that the individual mandate is unconstitutional, Vinson unwittingly demonstrates the weakness of both the legal and the moral case against the mandate.

The crux of Vinson’s argument is a distinction between “activity” and “inactivity” for the purpose of determining whether Congress has the power to create an individual insurance mandate under its “Commerce Clause” power. Vinson is picking up on the argument of the law’s opponents, who argue that Congress has no power to regulate “inactivity” under the Commerce Clause, only commercial activity. As Vinson concedes in a moment of candor, no previous Supreme Court opinion turns on this distinction. Indeed, no court ever even raised the possibility of such a distinction before now. Vinson is therefore obligated to explain why the distinction is relevant. Without an activity/inactivity distinction, he argues, “it would be virtually impossible to posit anything that Congress would be without power to regulate.” And if Congress can regulate a “passive individual for failing” to do something, “we would have a Constitution in name only.” Congress, Vinson worries, could even “require that people buy and consume broccoli.” Totalitarianism begins at “Eat your greens!”

This is stirring stuff—if you think that people have a basic right to be free of regulation in some sphere of commercial decisions. Vinson’s argument rests on a claim about a right to be let alone with respect to the decision about whether to pay for some kind of health insurance. It is a very particular kind of economic libertarianism in judicial diktat form.

The right to be let alone is an immensely appealing in all quarters of the political spectrum. But conservatives and progressives have very different ideas of what that freedom encompasses: the right to not pay for health insurance but the duty to pay for the world’s largest military? The right to carry a gun or the right to lifelong partnership with the person you love, whatever their gender? Vinson’s opinion is a case study for why one particular kind of economic libertarianism should not and cannot stand as law or national ethic.

Take first Vinson’s claim that absent judicial constraint of the power to regulate “inactivity,” Congress will have limitless power: As Andrew Koppelman has nicely explained, the Court has previously found ways to limit Congress’s power without reliance on an activity/inactivity distinction. For example, the Court has invalidated laws that regulate criminal activity with no national repercussions, and laws that “commandeer” state governments. Vinson can conjure the specter of an unlimited federal leviathan only by ignoring those inconvenient cases. And in order to make his parade of horribles work, he has to make the implausible assertion that there is no difference between the national market for health insurance and the national market for broccoli. No one, of course, really thinks that decisions to forgo broccoli cost the government $43 billion in uncompensated care annually.

Vinson also has to ignore the fact that the so-called mandate is not, in fact, direct regulation: a decision to forego coverage means a person has to pay a higher tax rate. If Vinson is correct that government cannot penalize inactivity with a tax, it would follow that tax penalties for failing to get married and failing to buy a house are unconstitutional. I look forward to the Tea Party manifesto that supports the marriage penalty and the abolition of the mortgage interest exception.

The second step in the argument—that the decision protects the right to be let alone—is equally flawed. For Vinson’s decision in fact does not protect people’s right to be let alone even on the terms he claims. It is canonical constitutional law that limits to Congress’s power are there to preserve space for the states to act. Striking down a federal law does not protect liberty per se, as much as leave the matter to the states. Any state can still enact a mandate. Vinson’s opinion does not explain why healthcare is particularly suited to state regulation and unsuited to federal action—the actual basis of the founders’ views on the Commerce Clause.

Worse, unless Vinson is planning on invalidating Medicaid and Medicare, his opinion has nothing to say about the federal government’s power to eliminate that same supposed constitutional liberty by taxing to create a public health system. The so-called right to be let alone is an illusory byproduct of our current politics, which stalled on the public option in favor of a mandate that was initially a Republican idea.

The peculiar libertarian premises on which Vinson’s opinion rest, that is, are legal phlogiston. Progressives now have an opportunity to show it’s not just his legal reasoning that’s flawed. They also have a chance to show that the idea of liberty at work in Vinson’s opinion is selfish, short-sighted and incoherent. This means turning attention to the human costs of our current healthcare system, and the way Vinson’s claimed liberty fits into the larger constellation of values espoused by Tea Party activists. Engaging in that task will be of far more use than getting caught up in false debates about judicial “activism.”