All the while, the ideal of universal care has revolved around two poles. In the 1930s, liberals imagined a universal right to health care tied to compulsory insurance, like Social Security. Johnson based Medicare on this idea, and it survives today as the “single-payer model” of universal health care, or “Medicare for all." The alternative proposal, starting with Eisenhower, was to create a market for health care based on private insurers and employers; he locked in the tax break for employee health benefits. Nixon came up with notions of prepaid, competing H.M.O.’s and urged a requirement that employers cover their employees. Everything since has been a variation on one or both of these competing visions. The plan now emerging from the White House and the Democratic Congress combines an aspect of the first (the public health care option) with several of the second (competing plans and an employer requirement to “pay or play”).

Devising a plan is easy compared with the politics of getting it enacted. Mere mention of national health insurance has always prompted a vigorous response from the ever-vigilant American Medical Association; in the 1930s, the editor of its journal equated national health care with “socialism, communism, inciting to revolution.” Bill Clinton’s plan was buried under an avalanche of hostility that included the now legendary ad featuring the couple Harry and Louise voicing their fears that the Clinton plan would substitute government for individual choice — “they choose, we lose.”