2022The president was Lyndon B. Johnson, and Soviet Union tanks had just rolled into Czechoslovakia on Aug. 20, 1968. Johnson’s call was to Richard M. Nixon, the Republican nominee for president. Nixon had already been alerted by his foreign policy adviser Richard V. Allen, who immediately called Nixon at his Fifth Avenue apartment, where Nixon had gone to bed early after a campaign trip. “Around 9 o’clock I woke him up” with news about the Soviet invasion, Allen said in a 2002 oral history interview at the University of Virginia’s Miller Center.