A few hours before the inauguration ceremony, the prospective president receives an elaborate and highly classified briefing on the means and procedures for blowing up the world with a nuclear attack, a rite of passage that a former official described as “a sobering moment.” Secret though it may be, we are at least aware that this introduction to apocalypse takes place. At some point in the first term, however, experts surmise that an even more secret briefing occurs, one that has never been publicly acknowledged. In it, the new president learns how to blow up the Constitution.

The session…