When Harry S. Truman enlisted in the army in World War I, he was struck by the number of men deemed unfit for service due to poor health.

“He felt it was a reflection of inadequate health care for parts of the population,” says Randy Sowell, an archivist at the Harry S. Truman Presidential Library and Museum.

Poor people could receive assistance for health care from charity programs, and wealthy people could afford it—but Truman felt the middle class was left out and ill-served, Sowell explains. So shortly after Truman took over the presidency in 1945, he proposed what he considered to be a practical and reasonable solution: health care for all, paid for through a type of payroll tax.

In a draft message to Congress in 1947, Truman wrote: “Healthy citizens constitute our greatest natural resource, and prudence as well as justice demands that we husband that resource. … as a nation we should not reserve good health and long productive life for the well-to-do, only, but should strive to make good health equally available to all citizens.”

The details of the plan, which became the Wagner-Murray-Dingell Bill, were never hashed out because it never even made it to a vote. Truman later called it the greatest disappointment of his presidency.

Truman saw his plan as an expansion of some aspects of the New Deal, a continuation of what he felt President Franklin Roosevelt would have done if he’d lived. But during a time of mounting fear of socialism, the American Medical Association (AMA) campaigned against the plan, concerned about doctors losing autonomy to government.

It even hired a P.R. firm to fight the idea, signaling the beginning of modern political propaganda campaigns, says Beatrix Hoffman, a professor of history at Northern Illinois University and the author of the book Health Care for Some. It was the largest and most expensive campaign of its time. Some of the propaganda took the form of comic strips featuring lines of patients stretching outside clinics and a robot delivering health care.

Although Truman made it clear the U.S. plan would not mirror the National Health Program in Britain, that seed of fear that doctors would become subject to politicians had been planted.

Other medical organizations latched on to the AMA stance, including the American Dental Association (ADA) and the National Physicians Committee. A telegram from May 31, 1947 to “physicians” and “dentists” from the National Physicians Committee warned: “Shall the independent professional status of physicians, dentists, nurses and medical technicians be maintained or—will you become a servant of a government agency taking orders from a departmental bureaucrat?”

It all left Truman steaming, feeling that the plan was completely mischaracterized, Sowell says.

“He never really got over that anger at the AMA,” Sowell says. “That seems to have especially rankled him.” At one point Truman wrote to a congressman, “At the proper time, we will take the starch out of them,” referring to the AMA.

Even without the negative campaigning, it was a hard time to get any progressive legislation passed. In 1945, the House and Senate were controlled by Democrats, but southern Democrats tended to vote conservatively. And Republicans regained control of both the House and the Senate in the midterm elections of 1946.

Truman’s efforts weren’t all for naught. The Hill Burton Act, passed in 1946, provided federal funds to build hospitals. Ironically, that ended up backfiring somewhat, Hoffman says, because it kept hospitals in private hands.

Years later, in 1965, President Lyndon B. Johnson traveled to the Truman Library in Independence, Missouri, to sign Medicare into law with Truman sitting next to him. Johnson credited Truman as “the real daddy of Medicare.”