In the fifty years since Medicare was enacted, Congress has not, with two exceptions in the 1970s, extended Medicare beyond the elderly. In those fifty years Congress has not even engaged in a serious discussion about expanding Medicare beyond the elderly. This disinterest persisted even during those periods when national health insurance was at the top of the national agenda. In other words, even when the conditions for health care reform were promising, Congress did not make Medicare-for-all a prominent option. In recent years, there has been at least as much discussion about raising Medicare's eligibility age as there has been about expanding the program to even a small fraction of the non-elderly.
Marmor, Theodore R. and Sullivan, Kip
"Medicare at 50: Why Medicare-for-all Did Not Take Place,"
Yale Journal of Health Policy, Law, and Ethics:
1, Article 9.
Available at: http://digitalcommons.law.yale.edu/yjhple/vol15/iss1/9