It was a case of the dog that didn’t bark.

For 90 minutes on Monday, Donald Trump and Hillary Clinton clashed in their first presidential debate on a full range of issues. But meriting not a single mention? Obamacare.

The Affordable Care Act ripped apart the nation and dominated political argument for several years. But now, six years after enactment, Obamacare isn’t on the radar screen during this election. And for good reason: The predicted apocalypse has not occurred.

Remember that talk of Obamacare forcing employers to cut back on workers’ hours and even “phase out full-time work”?

Didn’t happen. A thorough study by the nonpartisan Kaiser Family Foundation found that the law’s impact was, if anything, toward more full-time work.

Remember the talk about the “job-killing government takeover of health care”?

The U.S. economy has added 15.1 million private-sector jobs over the past 78 months.

Remember how “30 million people” were going to lose their employer-based health insurance and be thrown into the Obamacare exchanges?

The number of people insured by employers, about 150 million, has hardly budged.

The alarms about Obamacare adding trillions to deficits?

Deficits are down, and Medicare cost increases are below forecasts.

As for Obamacare driving up the cost of health care, premium increases in employer-based insurance were just 3 percent for 2016 — the latest in a string of historically low annual increases.

GOP leadership in the House of Representatives are introducing a plan to replace the Affordable Care Act. Here's what the proposal wants to change. (Jenny Starrs/The Washington Post)

Oh, and we’re still waiting for that first “death panel” to convene.

The headlines of late have been about big jumps in premiums in the Obamacare exchanges, health insurers quitting the exchanges and Obamacare co-ops failing. The health-care exchanges under Obamacare are indeed fraught with problems and never fully recovered from the disastrous Obamacare rollout. That leaves the widespread impression that the Affordable Care Act is foundering. “If it rains in D.C.,” Health and Human Services Secretary Sylvia Mathews Burwell told me, “it’s the Affordable Care Act.”

But only 11 million of the more than 280 million Americans with health insurance are in the exchanges. And of those 11 million, only a bit more than 2 million, primarily those in rural areas, are finding themselves without competitive plans to choose from.

Obamacare extended health insurance to 20 million people who were previously uncovered, and of those, only about 6 million get their insurance through the exchanges; the rest are covered because of the expansion of Medicaid, because they are young adults now covered on their parents’ plans, or because of other reforms.

“The worst predictions of what might happen under the law have by and large not happened,” said Drew Altman, president of Kaiser, which takes no position on the law. The main components of the law — expanding coverage and getting rid of insurance market abuses such as lifetime caps on benefits and refusal of coverage for preexisting conditions — “have been very successful,” he said.

Exchanges are struggling in part because employers didn’t dump workers onto them, as critics predicted. Participation in the exchanges is only about half the predicted level. Even so, the exchanges work well in many places, and, Altman said, “only a minority of people in the marketplaces have a limited choice of plans or are experiencing these very high premium increases you read about.”

Americans remain split on Obamacare, but this is about partisanship and feelings about President Obama, not the law. Individual Republicans claim they’ve been personally hurt by the law, while Democrats say they’ve been helped. In reality, few have been affected one way or the other. Even doctors polled about Obamacare split along party lines. The few health-care issues that do register with voters, such as rising deductibles and drug prices, have nothing to do with Obamacare.

In normal times, lawmakers would help the couple of million who have been hurt by Obamacare, by using “risk stabilization” to give insurers incentives to stay in non-lucrative markets. They could also provide a government insurance plan — the dreaded “public option” — for such markets.

Instead, foes of the original law are sabotaging the marketplaces by refusing to implement such risk-stabilization plans the way they did with previous health-care changes. “We’re in a boat, somebody’s shooting holes in the boat and then they’re complaining that there’s water in the boat,” Burwell protested.

The irony here is that the “big government” parts of the program — expanding Medicaid, ordering coverage expansions and removing coverage limits and exclusions — are working just fine. What’s struggling is the law’s attempt to preserve the free market: the Obamacare exchanges.

There are still big problems in the U.S. health-care system. The biggest is that 27 million people still don’t have insurance. Lawmakers motivated by something other than vindictiveness could do more for them and for the small minority hurt by Obamacare.

Twitter: @Milbank

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