The Warren Commission wrote many pages on Lee Harvey Oswald's visit to the American embassy in Moscow shortly after his defection to the USSR. However, the Warren Report says nothing about the U-2, much less about Oswald's work for the U-2 project as an aviation electronics operator.
The Commissioners were informed by CIA deputy director Richard Helms that Oswald only worked near the U-2 hangar in Japan, tap-danced around Oswald's access to the U-2 in the Philippines, and concluded that Oswald had no "information regarding the U-2 or its mission."
The Warren Report does mention that Oswald told legend maker #4 consul Richard Snyder that he had "already offered to tell a Soviet official what he had learned as a radar operator in the Marines" (p. 693). However, the Commission concluded that since neither the FBI or the Navy prosecuted Oswald, the State Department had no basis to conclude that Oswald's statement was "anything more than rash talk". (p. 775)
Whitten makes it sound like the CIA heard about these threats after the U-2 went down on May 1, 1960. In fact, Snyder's report and Navy reports in early November 1959 describe Oswald's threat to provide radar secrets to the Soviets, and the CIA had copies of these reports in their files right after Oswald left the American embassy on October 31.
The CIA's position was that "Since Oswald was a former Marine and a U.S. citizen, his defection was of primary interest to the State Department, the FBI, and the Navy Department. CIA does not investigate U.S. citizens abroad unless we are specifically requested to do so by some other Government security agency. No such request was made in this case."
This CIA officer is Ann Egerter, an analyst at the small, super-secret Counterintelligence Special Investigations Group (CI/SIG). Egerter called CI/SIG "the office that spied on spies". Her boss, legend maker #1 CI chief James Angleton, admitted that one of CI/SIG's purposes was to monitor defectors.
An FBI officer is also playing close attention - Marvin Gheesling, a supervisor at FBI Headquarters.
Oswald and the Moles
The October 31 and November 2 memos prepared by Snyder and his colleague Ed Freers about Oswald's defection are used by Ann Egerter, legend maker #5 , to fill Oswald's file with items of false information known as "marked cards". "Marked cards" are designed to capture a mole who spreads the information to unauthorized individuals.
The "marked card" technique has been around for a long time. Peter Wright in Spycatcher refers to this method as a "barium meal". Tom Clancy in Patriot Games calls this trick a "canary trap". Author Peter Dale Scott mentions that the "marked card" was one of the methods used to try to catch the infamous CIA mole Aldrich Ames during the 1990s. The marked card didn't work because Ames himself was the chief of the CIA's Soviet Russia counterintelligence staff.
Keep in mind that when Snyder prepared his reports, he was a trained observer and reporter of minutiae that the average person would not notice. This "Collinwood St." entry was just one of several misspellings and errors that were purposeful and not accidental. This deliberate error was a "marked card" to see if a mole leaked this information elsewhere.
Two days later, the November 2 dispatch prepared by Freers and Snyder adds three more marked cards to the deck. One was that Oswald was "discharged" from the service. Another was that Oswald's highest grade was corporal. The third was that Oswald applied for his passport in San Francisco.