IN THE days before the health care bill was passed, President Obama vowed it would “end the worst practices of insurance companies. . . insurance companies will be banned forever from denying coverage to children with pre-existing conditions.’’

When the bill passed last week, House Speaker Nancy Pelosi proclaimed, “We are hearing from families who are so thrilled because no longer will their children be denied coverage because they have a pre-existing condition. That starts this year.’’

Senator Tom Harkin of Iowa said, “You have a guarantee that your kids will be covered even if they have a pre-existing condition. . . These guarantees are not a promise. They are part of the law right now. And we are not going to let them take it away from the American people.’’

But in the insidious underworld of health care, forces are already trying to take this guarantee away from the people. Most notably and shamelessly, insurance companies are attempting to say that they actually do not have to insure all children with pre-existing medical conditions by this fall.

Last week, the Associated Press and Congressional Quarterly reported the first weasel words from insurance industry officials that the language in the law allows them to duck away from full coverage of sick children. Insurers say they read the law to mean that, sure, if we offer insurance to a family, we cannot discriminate for children’s pre-existing conditions. But, ah, they say, there is nothing in the law that says we have to offer insurance to the family in the first place until 2014, when insurance companies have to accept all Americans for coverage, regardless of medical conditions. The dispute concerns families who lack employment-based insurance and seek coverage in the non-group market.

The industry take on this sounds like the Peter Sellers “Pink Panther’’ routine where he sees a dog at the hotel door and asks the clerk if his dog bites. The clerk says no; the dog bites; Sellers re-questions the clerk and the clerk says, “but that is not my dog.’’

The insurance companies are saying, “but that is not my policy,’’ and in real life, it is American children and their parents about to be bitten again, at a time when the health burdens of children in our epidemic of obesity and explosion of diabetes are rising.

Insurance industry lawyer William Schiffbauer told the New York Times, “The fine print differs from the larger political message. If a company sells insurance, it will have to cover pre-existing conditions for children covered by the policy. But it does not have to sell to somebody with a pre-existing condition. And the insurer could increase premiums to cover the additional cost.’’

Thus, the undermining is already underway. On one hand, the insurance industry purports to be a team player. Since 2008, its top lobbying group, America’s Health Insurance Plans, has claimed it was ready to stop denying coverage to people with pre-existing conditions. But, of course, that is with the minor detail that Congress must let private insurers remain the only providers of health insurance.

The industry bitterly fought any attempt to have a public option that could compete with its outrageous rises in premiums. The government reported earlier this year that five top insurers, under current practices, scored a 56-percent rise in profits last year, totaling $12.2 billion.

The Obama administration is aware of the dispute. White House press secretary Robert Gibbs said last week that Health and Human Services Secretary Kathleen Sebelius will soon issue regulations to assure “that the term ‘pre-existing’ applies to both a child’s access to a plan and his or her benefits once he or she is in a plan.’’

They need a fix quick, because look who’s talking now, as if he really cares. Senate Minority Leader Mitch McConnell, who did his best to destroy the bill and protect the old system, said, “Just one day after the president signed this bill into law, we got word that one of its celebrated early features — a ban on discriminating against children with pre-existing conditions — won’t immediately protect children after all.’’

This loophole needs to be closed to ensure sick children the medical care insurers would prefer to deny them.

Derrick Z. Jackson can be reached at jackson@globe.com.

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