Various conspiracy theories allege that U.S. government officials had advance knowledge of Japan's December 7, 1941, attack on Pearl Harbor. Ever since the Japanese attack, there has been debate as to why and how the United States had been caught off guard, and how much and when American officials knew of Japanese plans for an attack. In September 1944, John T. Flynn, a co-founder of the non-interventionist America First Committee, launched a Pearl Harbor counter-narrative when he published a 46-page booklet entitled The Truth about Pearl Harbor, arguing that Roosevelt and his inner circle had been plotting to provoke the Japanese into an attack on the U.S. and thus provide a reason to enter the war since January 1941. Several writers, including journalist Robert Stinnett, retired U.S. Navy Rear Admiral Robert Alfred Theobald, and Harry Elmer Barnes have argued that various parties high in the government of the United States and the United Kingdom knew of the attack in advance and may even have let it happen or encouraged it in order to ensure America’s entry into the European theatre of World War II via a Japanese–American war started at "the back door". However, the Pearl Harbor advance-knowledge conspiracy is rejected by many historians as a fringe theory. Ten official U.S. inquiries The U.S. government made nine official inquiries into the attack between 1941 and 1946, and a tenth in 1995. They included an inquiry by Secretary of the Navy Frank Knox (1941); the Roberts Commission (1941–42); the Hart Inquiry (1944); the Army Pearl Harbor Board (1944); the Naval Court of Inquiry (1944); the Hewitt investigation; the Clarke investigation; the Congressional Inquiry (Pearl Harbor Committee; 1945–46); a top-secret inquiry by Secretary of War Henry L. Stimson, authorized by Congress and carried out by Henry Clausen (the Clausen Inquiry; 1946); and the Thurmond-Spence hearing, in April 1995, which produced the Dorn Report. The inquiries reported incompetence, underestimation, and misapprehension of Japanese capabilities and intentions; problems resulting from excessive secrecy about cryptography; division of responsibility between Army and Navy (and lack of consultation between them); and lack of adequate manpower for intelligence (analysis, collection, processing). Investigators prior to Clausen did not have the security clearance necessary to receive the most sensitive information, as Brigadier General Henry D. Russell had been appointed guardian of the pre-war decrypts, and he alone held the combination to the storage safe. Clausen claimed, in spite of Secretary