The Supreme Court is much on Mitch McConnell’s mind these days. The Senate minority leader, a Kentucky Republican, just finished reading Jean Edward Smith’s biography of the great Chief Justice John Marshall.

The book, a gift from the current chief justice, John Roberts, reminded McConnell that disagreement over the scope of the congressional power to regulate commerce among the states “goes back to the beginning of the country.”

The court is again grappling with the issue this week, as it hears arguments about the constitutionality of the health-care legislation that President Barack Obama signed two years ago. McConnell plans to attend part of the oral argument. “The president doesn’t want to talk about it,” says McConnell, but his fellow Senate Republicans are happy to. They will be making a point of it this week and next.

McConnell is known as a crafty insider, rather than a populist rabble-rouser, but sitting in his office in the Capitol he speaks of the health-care law in the accents of the Tea Party. It is “the single-worst legislation that’s been passed in the time I’ve been here,” he says. (He was first elected to the Senate in 1984.) “Obamacare was really the metaphor for all of the excess of this administration and a very compliant Congress in ’09 and ’10.”

Intrusive and Bossy

Supporters of the law have repeatedly predicted that Americans would soon come to like it. “They are genuinely perplexed at how unpopular it is,” McConnell says. They believed, he adds, that it would become as sacrosanct as Social Security and Medicare, not realizing that it would come to be seen, unlike those programs, as intrusive and bossy.

Democrats often tout two provisions of the law: the requirement that insurers treat people with pre-existing conditions the same as people without them, and the requirement that they allow young adults to stay on their parents’ plans. “I’ll concede those test well,” McConnell says. “What about the other 95 percent of the bill?” The popular provisions do not seem to be scaring his Republican colleagues away from supporting repeal: “This is an issue where there are no divisions,” he says.

McConnell argues that if the court upholds the requirement for individuals to purchase health insurance, it would subvert the constitutional order because the federal government would be able to do anything the Constitution doesn’t specifically prohibit. On the theory underlying the mandate, he argues, in common with other opponents, the federal government could order people to eat carrots, or quit smoking, or lose weight.

But McConnell doesn’t worry that a court decision to uphold the mandate will make the law more popular or help the Democrats. Most of the arguments Republicans made before the vote on the law concerned its unwisdom rather than its unconstitutionality, and no court decision can undermine those arguments, he says. If the court keeps the law and McConnell becomes Senate majority leader, he vows that “the first item up would be to try to repeal Obamacare.”

But he doesn’t favor comprehensive legislation to replace it. “We would want to more modestly approach this with more incremental fixes,” he told me. “Not a massive Republican alternative.”

Two ideas McConnell mentions are allowing people to purchase health insurance across state lines and reforming medical-malpractice laws. Neither idea would do much to increase coverage, and McConnell didn’t mention one idea -- changing the tax treatment of health insurance -- that would, perhaps because his party hasn’t reached a consensus on it.

Election Issue

If McConnell shares the jitters of many Republicans about the presidential race, he hides it well. And the president’s record on health care is one of the reasons for his optimism. “None of us has a clue what the Supreme Court will do,” he says. “I don’t know what the unemployment rate will be on Election Day. But I’ll bet you that Obamacare will be unpopular in November.”

Signing the health-care legislation was probably the most consequential action Obama has taken, yet it seems likely that both major presidential candidates will be hesitant to talk about it. Obama will avoid the topic because it’s unpopular, while his probable challenger, Mitt Romney, will do the same because the health-care law he himself signed as governor of Massachusetts bears an embarrassing resemblance to it.

McConnell faces no such constraints. He is going to do what he can to keep the issue alive, whatever the Supreme Court decides.

(Ramesh Ponnuru is a Bloomberg View columnist and a senior editor at National Review. The opinions expressed are his own.)

Read more opinion online from Bloomberg View. Today’s highlights:

The editors on health-care reform’s day in court and Russia’s objections to missile defense. Jeffrey Goldberg on Israel’s overconfident leaders. Edward Glaeser on regulation that can aid entrepreneurs. Simon Johnson and James Kwak on why the U.S. abandoned the gold standard.

To contact the writer of this article: Ramesh Ponnuru at rponnuru@bloomberg.net

To contact the editor responsible for this article: Timothy Lavin at tlavin1@bloomberg.net