After painstakingly documenting how the country’s security agencies played the Warren Commission, Shenon and Willens both explain away this monumental deception by claiming that the country’s intelligence apparatus was simply trying to hide its embarrassing failure to protect the president. But there’s another, more disturbing conclusion that is left hanging in the air. If the CIA was just trying to hide embarrassing mistakes back in the 1960s – security lapses that have long since been exposed — what is the agency still trying to conceal?