Sens. Susan Collins, R-Maine, and Lisa Murkowski, R-Alaska, stood tall against partisan pressure in voting to stop a disastrous health care bill. Now, in the context of the tax bill, they committed themselves to repealing the individual mandate, causing grave economic disruption to the individual market and leaving 13 million fewer insured.

The excuse that they have gotten assurance that President Trump will back the legislation to preserve cost-sharing reduction subsidies to insurers doesn’t make sense. Timothy Jost at Health Affairs explains:

“The two bills are the Alexander-Murray bipartisan health reform bill, which would provide funding to reimburse insurers for reducing cost sharing for low-income enrollees for 2018 and 2019, and another bill that Sen. Collins is co-sponsoring with Sen. Bill Nelson, D-Fla. The Collins-Nelson bill would provide $2.25 million in funding for 2018 and for 2019 for states that obtained 1332 innovation waivers to institute reinsurance programs.

“The assumption underlying this trade-off is presumably that adoption of Alexander-Murray and Collins-Nelson would offset the damage done to the individual market by repeal of the individual mandate. However, on Nov. 29, 2017, the Congressional Budget Office released a letter to the Senate Health, Education, Labor and Pension Committee ranking member, Sen. Patty Murray, D-Wash., confirming that adoption of the Alexander-Murray bill would not begin to offset the dramatic increase in the number of uninsured that would be caused by the individual mandate repeal.

“In its Nov. 8, 2017, report on individual mandate repeal, the CBO estimated that repeal would cause 4 million individuals to lose coverage by 2018 and 13 million by 2025. In its Oct. 25, 2017, analysis of the Alexander-Murray bill, the CBO estimated that it ‘would not substantially change the number of people with health insurance coverage, on net, compared with (the CBO’s) baseline projection.’ … The CBO’s Nov. 29 projection, therefore, that Alexander-Murray will not begin to offset the coverage losses of the individual mandate repeal is consistent with its earlier projection that cost-sharing reduction funding has little effect on coverage, one way or the other.”

As for the Collins-Nelson bill, a Rand Corp. study calculated that it would increase coverage by 1.2 million (not enough to offset the 13 million who will lose coverage) and would reduce premiums by 3.9 percent, not enough to offset “the 10 percent premium increases that the CBO predicts would be attributable to the individual mandate repeal.”

Politically, it’s foolish for Collins and Murkowski to give way, since the White House has already said the individual mandate repeal could come out of the Senate tax bill. (It was not in the House bill, of course.) Collins and Murkowski are being less protective of health care coverage in this instance than Office of Budget and Management Director Mick Mulvaney.

Another argument – that the repeal of the individual mandate isn’t the same as throwing people who already have insurance off insurance – is entirely specious. The individual mandate repeal unwinds the exchanges, allowing young and healthy people to stay out of the risk pools, making coverage more expensive and even unaffordable for those who remain. Surely, Collins and Murkowski know this to be the case from the Obamacare repeal debate.

Simply put, as the Center on Budget and Policy Priorities found: “Pairing mandate repeal with the Collins-Nelson bill, or a similar approach … would not change the fact that repealing the mandate would drive up uninsured rates. That would weaken access to care, health and financial security for millions of people. It would also substantially raise uncompensated care costs, which would ultimately be borne by providers, other health care consumers and taxpayers.”

None of this addresses the damage the bill may do to Medicaid and Medicare. Because of the deficits it creates (an issue that has thrown the entire legislative process into confusion), there may be a $25 billion sequester in Medicaid and Medicare funding in 2018 alone under the so-called pay-as-you-go rules. Collins has said she’d oppose that, but her colleagues do not show the same concern.

It should behoove Collins and Murkowski to reconsider their position as the rest of the bill is now being reworked. Patient advocates, hospitals and doctors groups remain mystified by their about-face. Democrats are incredulous that a provision that is not a must-have for Republicans leadership or the White House is getting the support of these two lawmakers.

Because they’ve gone along with this gambit, the good will they gained in the health care debate will evaporate. Collins and Murkowski had the perfect opportunity to reclaim their role as guardians of health care coverage – by committing to voting in favor of the tax bill, they’ve forfeited that chance.