A lot of folks breathed a sigh of relief when the Affordable Care Act banned health insurers from giving the boot to people who suffer from expensive medical conditions.

Now we can start worrying again.

On Thursday, the Trump administration announced that it will not defend the ACA in a federal lawsuit that, if successful, would bring back the days when people who faithfully paid for their health insurance year after year could lose coverage just because they or a family member developed a serious medical condition.

EDITORIAL

The decision by the Justice Department is part of a long-running effort by the Trump administration and congressional Republicans to sabotage the ACA, also known as Obamacare. It’s also another broken promise by President Donald Trump, who has repeatedly vowed — no matter what — to protect people with pre-existing medical conditions.

The court case filed by Texas and 19 other states makes a claim that many legal observers consider unfounded, even preposterous — that Congress’ decision last year to end the mandate that required individuals to buy health insurance invalidated important protections elsewhere in the law.

In an extraordinary development, three career Justice Department lawyers withdrew from the case just before the decision was announced. That means defending the law will be up to states that have entered the case as ACA supporters.

After its major provisions went into effect in 2014, the Affordable Care Act achieved important successes, including substantially reducing the number of Americans without health insurance and protecting people who became ill from having their health insurance raised to unaffordable levels or simply taken away.

Since then, congressional Republicans and, more recently, the Trump administration have chipped away at the law, and the protections it has given to ordinary Americans, even as a higher percentage of Americans has come to support the law.

The Trump’s administration also, more broadly, is displaying contempt for the rule of law. The Justice Department almost invariably defends in court the laws that Congress has passed.

Under President Barack Obama, the Justice Department declined to enforce the Defense of Marriage Act because it denied federal benefits to same-sex couples, but that was a central social issue the country was attempting to resolve.

Refusing to enforce the widely supported Affordable Care Act on a narrow and debatable legal point, however, suggests the Justice Department will feel free enforce only those laws it wishes to despite what Congress has passed and a president has signed.

And, of course, even Trump and the GOP attempt to eviscerate Obamacare, they still have no credible plan to replace it.

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