Princeton healthcare economist Uwe Reinhardt writes in Vox that the Republicans can repeal the Affordable Care Act but they can’t repeal the mathematics of healthcare and especially the huge expense of caring for the chronically ill. He notes that:

In 2013, 10 percent of patients accounted for nearly two-thirds of healthcare spending and 1 percent accounted for more than a fifth of spending.

He says that a central question is: “Which treatments should high-cost patients receive and how should they be financed?’’

The ACA subsidizes care for high-cost patients through  such provisions as the individual mandate and community rating premiums, which  force younger, healthier individuals to pay more than their “fair” share in premiums. Republican ideology against the ACA targets rising premiums, but, he notes,  “the health insurance debate will be driven mostly by actuarial logic, not ideology.”

The GOP will face the problem of how to finance healthcare for the very sick  — and generally older — part of the population. Giving everybody a refundable tax credit, as proposed by House Speaker Paul Ryan’s “A Better Way,” wouldn’t do much for a very sick person charged very high actuarially “fair” premiums.

The complaints by younger, healthier people about what they see as their too-high premiums and co-pays ignore the reality of all health insurance, if it is to work  — that the healthier must help subsidize the unhealthy, and that younger, healthier people should bear in mind that they, too, will eventually get sick as they age.

As Vox’s Sarah Kliff points out, Mr. Ryan’s proposal “makes insurance better for people who are young and healthy. It makes insurance worse for people who are old and sick.”