We understand that congressional Republicans hate the Affordable Care Act. They voted dozens of times to repeal it even when there was no possibility of a repeal passing the Senate or getting signed into law by President Barack Obama.

Now, of course, they have control of both houses of Congress and an incoming president as hostile to Obama’s signature health care reform as they are. They are anxious to fulfill their promises to get rid of the act — even as they have no idea how they can do that without throwing 20 million newly insured Americans out of coverage.

Republicans should move far more cautiously than they are showing any willingness to do thus far.

The Denver Post editorial page supported passage of the Affordable Care Act, though we knew it was not perfect. We wished it had passed with bipartisan support and better cost-control provisions. But Democrats didn’t need bipartisan support, so they barreled it through largely without Republican votes.

Now Republicans are in the driver’s seat, and they appear prepared to make the same mistake.

And it would be a mistake.

It’s easy to forget now, but the status quo prior to passage of the Affordable Care Act was not good. Forty million Americans had no insurance, and could be bankrupted by an unexpected illness or accident. Millions more could not get new insurance because of pre-existing conditions. Children could only stay on their parents’ insurance until they turned 21.

This system was bad for workers, often locking them into their jobs. It was bad for hospitals, which lost millions upon millions of dollars in uncompensated care. It was bad for the insured, who paid higher prices to make up the costs of caring for the uninsured. It was bad for the uninsured, who could be ruined by bills they could never hope to pay. Mostly, it was the insurance companies who benefited.

The Affordable Care Act still has some problems. The exchange markets are not functioning as well as they should, for example, leading to some hefty premium increases this year. Costs, especially for prescription drugs, continue to skyrocket.

But the law is not nearly the disaster its opponents are trying to paint it as. Even as Republicans go full steam ahead on their repeal efforts, 8.8 million people signed up for insurance plans on the federal exchange, a new record. Its cost-containment measures, inadequate as they were, have had some success in lowering the rate of health care inflation.

As opponents pointed out at the time the Affordable Care Act was passed, the health care sector is an enormous part of the American economy — nearly a fifth. There is no doubt that the Affordable Care Act was hugely disruptive.

But that’s all the more reason for caution now. Repealing the Affordable Care Act would be another huge disruption — especially with the “replace” part of the “repeal and replace” plan so murky.

Any reform as sweeping as the Affordable Care Act takes some time to get right. Let’s not rush into another hugely disruptive process over health care. Let’s get it right.

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