WE WOULD congratulate Pennsylvania Gov. Tom Corbett (R), if it were seemly to commend public officials for doing the obvious.

On Thursday, Mr. Corbett finalized a bargain with federal officials to expand Medicaid, the state-federal program that provides health-care coverage to low-income Americans, in Pennsylvania. Five hundred thousand needy Pennsylvanians stand to get care at almost no price to the state. Reform may even be revenue positive.

It should not have taken this long. But
Mr. Corbett’s example is still a useful one for other GOP leaders: Republicans can work with the feds to design Medicaid expansions that suit their states and address their policy concerns; irrationally rejecting federal money, as many continue to do, is the worst of all options.

Under the Affordable Care Act, the federal government is offering to pay nearly the whole cost of a broad health-care expansion for the poor through the existing Medicaid program. But state leaders must sign off on expansion within their borders and eventually kick in a little cash. Not all of them have cooperated. Unsurprisingly, expansion states have seen much more dramatic drops in their uninsured rate — 38 percent since last September — than the drop other states have managed — 9 percent. America’s uninsured population is increasingly concentrated in the 24 states that have not expanded Medicaid.

Anti-Obamacare Republicans have resisted on pretexts, threatening to leave more than 6 million Americans uncovered and more than $400 billion in expansion funds on the table over the next decade, according to the Urban Institute. Holdouts say cooperating will cost too much, but analysis after analysis says otherwise. Holdouts also say the feds might go back on the arrangement, but there is no comparable hand-wringing over the financing of other state-federal programs. They have various concerns about the design of the Medicaid program, but, as Mr. Corbett and other Republican governors have shown, the federal government will give them flexibility in how they design their expansions.

In Pennsylvania, for example, beneficiaries of expansion will have to pay premiums for their coverage. In Arkansas, participants will buy into private plans. In Michigan, they will be able to reduce their out-of-pocket costs by quitting smoking or making other lifestyle changes. True, federal officials have not accepted every demand Republicans have made. But they have been receptive to GOP ideas.

With Pennsylvania opting for expansion on GOP terms and Tennessee considering an expansion plan of its own, those Republicans who continue to hold out look increasingly like ideologically blinded fringe players. Virginia Republicans are a case in point. Offered compromise after compromise, they have refused to countenance any cooperation even as non-partisan analysts and moderate Republicans have pointed out that there is a clear right answer — for those who care about the merits.

Virginia’s General Assembly will meet next month to consider Medicaid expansion again. Relatively moderate Republicans are offering more compromise proposals. Lawmakers have many expansion designs to choose from. There is no rational reason to keep thousands of Virginians without access to health care.