Nearly three decades before the Affordable Care Act (ACA) was put on the precipice of repeal by the 2016 election of a unified Republican government, the Medicare Catastrophic Coverage Act (MCCA) was enacted with fanfare by one Congress and dismantled by the next. As the one social program terminated by Congress—also involving health care coverage expansions for millions of beneficiaries and imposing costs on identifiable constituencies—the MCCA experience could provide insights into the politics that define the fate of the ACA. This article compares and contrasts the two episodes, focusing on the political-institutional contexts of each case, the processes that produced the shifting coalitions from enactment to repeal, and the policy attributes that posed risks or provided protection to each program. The political-institutional contexts and the processes of coalition change could hardly have been more different for MCCA and ACA. However, they had some shared vulnerabilities stemming from program design. The ACA survived the political weakness inherent in its policy attributes due to its particular balance and timing of benefits and costs and by being shielded long enough by election results and the constitutional separation of powers to have its benefits take root.