I and others have written of the breach that grew between Jack and Bobby Kennedy and the covert operatives of the Central Intelligence Agency over the Kennedys’ repeated demands that the agency find a way to assassinate Fidel Castro. Cuba’s Communist leader was in the brothers’ sights before and after he survived the failed Bay of Pigs invasion of April 1961.

The Kennedys were media darlings despite that failure. Richard Helms, head of the agency’s covert operations, and his immediate staff understood that there was no turning down the mission. They had to keep trying to get rid of Castro–and they did keep trying–until the November 22, 1963, assassination of the president freed them of the task. I was told that the night of the Kennedy murder was a night of drinking and celebration for some of the clandestine operators in the agency.

I didn’t fully understand the depth of the CIA’s anger at the Kennedy brothers until I began talking to Sam Halpern, a retired senior aide to Helms. Halpern was known as a keeper of secrets who knew how to keep his mouth shut. Sammy was very old school: the only reason he ever talked to a reporter was to spread a lie. He was said to know the name of every foreign government official who had been recruited by the CIA and how much they were paid annually. If this information was not in his head, then it was in a mythical black book some believed he constantly carried on his person.

Halpern was not a talker and he was not my friend, to put it mildly, even in the 1990s, because of my reporting for the New York Times and the New Yorker about secret operations that included the explosive revelation of a book of CIA horrors–known internally as the Family Jewels–that was maintained by the agency. But Halpern was long retired and his name was in the telephone book. I called him and told him the magic words: I was writing a book on Jack and Bobby. He invited me for an early morning coffee at his suburban Virginia home. Over the next few months there were many more morning coffees. Sammy unloaded on me a litany of CIA operations ordered by the Kennedy brothers that went nowhere. Eventually he told me about the one event in 1962 that he viewed as the most egregious of them all. Over the objections of many in the operations bureau, Bobby Kennedy personally authorized the agency to assign a senior agent to his office for operations against the Mafia. These actions would not be carried out in America but in Sicily, the home of many powerful and brutal Mafia families.