It was always for our own good. It was always for a very good reason. It was always within the American tradition of this, that, or the other.

That’s what they’ve told us; that’s how they’ve patronized us, for generations, as the long tendrils of the federal government have spread and multiplied into every realm of American life. It had become so utterly unremarkable, this robotic and seemingly inexorable aggrandizement of federal power, that when Speaker Nancy Pelosi was asked, in 2009, where in the Constitution Congress was granted the authority to force people to buy health insurance, she didn’t even seem to understand the question. “Are you serious?” she asked. “Are you serious?”

But Judge Henry Hudson (don’t you love the historically resonant name?) was very serious when he ruled that the Constitution created a federal government of “enumerated powers,” and that limits on those powers have continuing force. He’s not only serious, he’s cautious and learned. And he represents something we wouldn’t necessarily have predicted back in 2008 when it seemed a new liberal hegemony would unfold over the next 25 years: a principled backlash against federal overreach. Those Tea Party protesters in their Founders costumes may have looked ridiculous to Nancy Pelosi and Harry Reid, but their interest in seemingly antique concepts such as limited government is showing up more and more. In just one month, a federal judge has ruled that the Commerce Clause cannot be stretched to cover absolutely everything the Congress wishes to do, and a chorus of limited-government voices has noisily protested the Federal Communications Commission’s attempt to assert control over the Internet.

It isn’t possible for the former speaker or her allies in the federal juggernaut to dismiss Judge Hudson as “astroturf.” In a carefully reasoned decision, he took note of Congress’s power to regulate under the Commerce Clause. “But these regulatory powers,” he ruled, “are triggered by some type of self-initiated action. Neither the Supreme Court nor any federal circuit court of appeals has extended Commerce Clause powers to compel an individual to involuntarily enter the stream of commerce by purchasing a commodity in the private market.” Judge Hudson continued, “The unchecked expansion of congressional power to the limits suggested . . . would invite unbridled exercise of federal police powers” whereas “Article I, Section 8 of the Constitution confers upon Congress only discrete enumerated governmental powers.”

Together with challenges to the health-care law mounted by 19 states, as well as differing judgments in other jurisdictions, the stage is now set for the Supreme Court to decide the issue. If the court decides, contra Judge Hudson, that the Commerce Clause can indeed be stretched to cover anything, it won’t be the first time. In 1942, the Court (just a few years after FDR’s court-packing plan) ruled that the Commerce Clause could justify the regulation even of intrastate commerce. “The marketing of intrastate milk,” wrote the Court in the 1942 Wrightwood Dairy case, “which competes with that shipped interstate would tend seriously to break down price regulation of the latter.”

An even more far-fetched bit of Court reasoning followed in Wickard v. Filburn (1942), in which the federal government fined a farmer who raised wheat for his own consumption. The rationale: By eating his own wheat, the farmer did not buy wheat, and this non-participation in the market for wheat affected interstate commerce. Those who cannot imagine the Court upholding a requirement that individuals buy a particular product (health insurance) should think again.

Since the New Deal, and particularly during the civil-rights era, the Commerce Clause has been interpreted capaciously to permit the government to do good (actual good in the civil-rights cases, perceived good in the New Deal cases). But no matter what the motive, the effect was to vitiate the Constitution’s principle of enumerated powers. A more limited understanding of the Commerce Clause emerged in the 1990s when the Supreme Court struck down the Gun-Free School Zones Act. The Court’s composition has changed since then.

But the mood of the country is changing too. Everywhere you look, assertions of power are being questioned. When the FCC announced plans to regulate the Internet in the name of so-called “net neutrality,” dozens of congressmen protested that the agency was exceeding its authority. Dissenting commissioner Robert McDowell dubbed it “jaw dropping interventionist chutzpah.” But the comment that captured the new mood of respect for limited powers came from Sen. Mitch McConnell. “The Internet,” he said, “should be left alone.” Yes, for starters.

— Mona Charen is a nationally syndicated columnist. © 2010 Creators Syndicate, Inc.