(continuing, after leaving out about one page, from near the top page 205 in the book...)
Hoover was soothed when [CIA director John] McCone agreed the main responsibility for the investigation fell on the Bureau. If the Bureau said there was no foreign plot, the CIA would play along -- especially since that was the answer the White House wanted publicized.
While the public record was being censored, however, Angleton was considering more carefully, and secretly, the specter of a possible KGB plot. Angleton was bothered by [KGB defector Anatoliy] Golitsyn's ominous [December] 1961warning about the KGB's planning to kill "a Western political leader," by the mystery of Oswald's travels in the USSR, and by other unresolved questions. CIA had heard, for example, that [KGB officer Valiery] Kostikov [believed at that time by FBI and CIA to be in charge of assassinations in the Western Hemisphere] had planned in advance to leave Mexico on November 22, and that a Cubana Airlines flight to Havana was delayed for six hours on the tarmac in Mexico City on the night of the assassination, awaiting an unidentified passenger [Miguel Casas Saez?].
The man had finally arrived at the airport in a twin-engine aircraft, then failed to go through Customs, where he would have had to identify himself by displaying a passport. The Cubana plane took off and the mysterious passenger rode in the cockpit to Havana, precluding any identification by the passengers. Mexican surveillance soon established that Kostikov had remained in Mexico City, but Angleton still wondered who the passenger had been, why he flew to Cuba on the day the president died, and why he had taken such pains to conceal his identity.
Similar questions swirled around Gilberto [Policarpo] Lopez, the Cuban-American who, by some reports to CIA, had been involved in Kennedy's death, and whose actions the FBI inexplicably failed to probe. Lopez had lived in Tampa, which was [rumoured Castro agent] Santo Trafficante's base of operations, and he had visited Cuba for several weeks during May 1962, precisely when Trafficante had claimed to be sending his agents into Cuba to poison Castro.
(continued ...)