Single-payer advocates counter that government-run health systems in other developed countries spend much less than the United States does on its complex public-private arrangement. They say that if the United States adopted a European model, it could expand coverage to everyone by realizing a mountain of savings with no measureable decline in health outcomes, in part because excessive administrative costs and profit would be wrung from the system.

In fact, the savings would be less dramatic; the Urban Institute’s projections are closer to reality. The public piece of the American health-care system has not proven itself to be particularly cost-efficient. On a per capita basis, U.S. government health programs alone spend more than Canada, Australia, France and Britain each do on their entire health systems. That means the U.S. government spends more per American to cover a slice of the population than other governments spend per citizen to cover all of theirs. Simply expanding Medicare to all would not automatically result in a radically more efficient health-care system. Something else would have to change.