On the night of Oct. 11, 1973, just days into the Arab-Israeli War and with the United States and Soviet Union on a seeming collision course, British Prime Minister Edward Heath tried to reach Nixon by phone to discuss the crisis.

"Can we tell them 'No?'" Kissinger asked his assistant, Brent Scowcroft, who had told him of the request from 10 Downing Street. "When I talked to the president, he was loaded."

"We could tell him the president is not available and perhaps he can call you," Scowcroft replied.