On this day in 1965, President Lyndon B. Johnson signed Medicare into law. While this was a landmark event, much needed to be revised and improved over the course of half a century.

Landmark laws don’t just mark the end of political struggles—they also start new ones. And even the most beloved and successful social programs in American democracy have taken time to work out. The 1935 blueprint for Social Security was profoundly incomplete (it excluded most working women and about 80% of African Americans in parts of the South). Social Security had its financial provisions substantially revised in 1939, experienced life-threatening interruptions in scheduled taxes and benefits during World War II, and did not really become taken for-granted until the period between the early 1950s and the mid-1970s, when taxes resumed and new beneficiaries and enhanced benefits were added.

Find out more about the evolution of Medicare, from its origins to the present, with Health Care Reform and American Politics: What Everyone Needs to Know by Lawrence R. Jacobs and Theda Skocpol.

Image Credit: “President Lyndon B Johnson signing Medicare Bill” by Executive Office of the President of the United States. Public Domain via Wikimedia Commons.