Kennedy rival Nixon left Dallas as JFK arrived in November 1963

In the post-midnight darkness, as Nov. 21, 1963, slipped into Nov. 22, 1963, a cold front that had carried Pacific moisture across the American Southwest approached Fort Worth and Dallas. Before dawn, the moisture began to fall in a misty drizzle — unremarkable except that it fell on the 35th, the 36th and the 37th presidents of the United States.

In downtown Dallas, behind durable drapery and metal Venetian blinds, former Vice President Richard Nixon slept alone in his suite at the Baker Hotel. Outside in the hallway stood a single Dallas police officer who was stationed at the nearby door of actress Joan Crawford to protect her from jewel thieves and autograph seekers.

It had been one year since Nixon’s political self-immolation. After he lost his 1962 comeback race for California governor, he resentfully told the press, “You don’t have Nixon to kick around anymore.” Now, he was a corporate lawyer visiting Dallas on behalf of his client, Pepsi-Cola....