Few living Americans can claim credit for the Constitution in the way that Birch Bayh can. Bayh, then a first-term senator from Indiana, chaired the Senate Judiciary Subcommittee on Constitutional Amendments at the time of President Kennedy's assassination. Vice President Johnson's succession to the Presidency left a vacancy in the vice presidency--a situation that had occurred after the other seven vice-presidential successions, but that was suddenly far less acceptable in the nuclear era, with a Cold War on. The crisis was exacerbated because the next two successors in line for the Presidency were 71-year-old House Speaker John McCormack and 86-year-old Senate President pro tem Carl Hayden, who had been chosen for reasons other than their fitness as Presidential successors.

The crisis was solved (up to a point, at least) by the twenty-fifth amendment, which was proposed in 1965 and ratified in 1967. "One Heartbeat Away" tells the story of the amendment's drafting, proposal, and ratification, which Senator Bayh presided over and shepherded. This book offers a rare insight, practically unique in modern times, into successfully resolving a structural dilemma of modern government by means of amending the Constitution. Presidents Eisenhower and Johnson, who were both very engaged in the issues and the process, contributed prefaces.

If you are interested in the twenty-fifth amendment and its legislative history, I also recommend "The 25th Amendment" by John D. Feerick. If you are interested in Presidential succession and disability generally, I recommend "Presidential Succession" by Ruth C. Silva and "From Failing Hands" by John D. Feerick.