NEW YORK, June 28 (Reuters Breakingviews) - The U.S. Supreme Court has upheld Obamacare with barely a legal ripple. Saving the president's landmark healthcare reform may roil electoral politics but won't change U.S. legal precedent much. Congress remains powerful, subject to some useful limits in the Medicaid context.

The justices affirmed the law by a 5-4 vote, focusing on its so-called individual mandate, the requirement that virtually all Americans buy medical insurance or pay a penalty. They bought the argument that the mandate isn't valid under the Constitution's Commerce Clause, because it regulates inactivity - the choice not to buy coverage. But it's legal under the taxing authority of Congress, the justices said, because the penalty is actually a tax. The court also shaved the federal government's ability to punish states that don't comply with the law's expanded Medicaid coverage.

The decision is a triumph for Obama and his signature legislative achievement. Rival Mitt Romney and the Republicans have used the ruling to step up calls for abolishing the law. Their criticism of the decision itself will probably stress its dangerous expansion of the federal government's power.

That may score political points, but legally it's off the mark. As the U.S. economy's complexity has grown, so has Congress' power to regulate it. Thursday's ruling merely clarifies that power without fundamentally changing it. The taxing authority is simply reaffirmed. And the explicit ban on regulating inactivity isn't a big deal, because Congress has so many means to desired ends.

Consider its ability to fund healthcare for the uninsured. Congress could have used an income-tax surcharge, and given a tax credit to anyone with insurance. Or it could have required each state to adopt its own mandate - as Massachusetts did when Romney served as governor - as a condition of receiving certain federal funding. Both approaches would pass constitutional muster.

In short, today's ruling is more Bush v. Gore than Roe v. Wade. In Roe, the high court reinterpreted liberty and transformed politics by upholding abortion rights. In Bush, the justices set little precedent with a vote-counting opinion that determined a presidency and, like this case, had profound political and economic consequences.

Despite harsh criticism of all three decisions, faith in the rule of law somehow survives. That's a welcome reminder of the Constitution's resilience amid political turmoil.

CONTEXT NEWS

- The U.S. Supreme Court on June 28 upheld President Barack Obama's healthcare reform, ruling by a 5-4 vote that Congress had the authority under its taxing power to require virtually all Americans to buy health insurance or pay a penalty. The landmark decision paves the way for the major provisions of the Affordable Care Act of 2010 to go into effect in 2014. 

(Reporting by Reynolds Holding, a Reuters Breakingviews columnist. The opinions expressed are his own.)

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