A party that loses a House seat can win it back two years later, as Republicans just proved. But a party that loses a legislative fight against a middle-class health-care entitlement never restores the old order. Pretty soon, Republicans will be claiming the program as their own. Indeed, one of their favorite arguments against this year’s health-care bill was that it would cut funding for Medicare. Now they’re pledging to rescind those cuts. In 30 years, they’ll be accusing Democrats of defunding Obamacare.

Most bills aren’t more important than elections. This one was. Take it from Mitch McConnell, the Senate Republican leader. Yesterday, in his election victory speech at the Heritage Foundation, he declared, “Health care was the worst piece of legislation that’s passed during my time in the Senate.” McConnell has been in the Senate for 26 years. He understands the bill’s significance: It’s a huge structural change in the relationship between the public, the economy, and the government.

Politicians have tried and failed for decades to enact universal health care. This time, they succeeded. In 2008, Democrats won the presidency and both houses of Congress, and by the thinnest of margins, they rammed a bill through. They weren’t going to get another opportunity for a very long time. It cost them their majority, and it was worth it.