Editing Federal Bureau of Investigation (section)

==== National security ====
Beginning in the 1940s and continuing into the 1970s, the bureau investigated cases of [[espionage]] against the United States and its allies. Eight [[Nazism|Nazi]] agents who had planned [[sabotage]] operations against American targets were arrested, and six were executed (''[[Ex parte Quirin]]'') under their sentences. Also during this time, a joint US/UK code-breaking effort called "The [[Venona project|Venona Project]]"—with which the FBI was heavily involved—broke Soviet diplomatic and intelligence communications codes, allowing the US and British governments to read Soviet communications. This effort confirmed the existence of Americans working in the United States for Soviet intelligence.<ref name="nsa">{{cite web |last=Benson |first=Robert L. |url=http://www.nsa.gov/publications/publi00039.cfm |title=The Venona Story |publisher=National Security Agency |access-date=June 18, 2006 |archive-url=https://web.archive.org/web/20060614231955/http://www.nsa.gov/publications/publi00039.cfm<!-- Bot retrieved archive --> |archive-date=June 14, 2006}}</ref> Hoover was administering this project, but he failed to notify the [[Central Intelligence Agency]] (CIA) of it until 1952. Another notable case was the arrest of Soviet spy [[Vilyam Genrikhovich Fisher|Rudolf Abel]] in 1957.<ref>{{cite book |last1=Romerstein |first1=Herbert |last2=Breindel |first2=Eric |title=The Venona Secrets, Exposing Soviet Espionage and America's Traitors |publisher=Regnery Publishing, Inc. |year=2001 |isbn=0-89526-225-8 |page=209}}</ref> The discovery of Soviet spies operating in the US motivated Hoover to pursue his longstanding concern with the threat he perceived from the [[American Left]].