Given that the U.S. was ‘privy’ to all Japanese secrets from the mid-1930s onwards, does one really expect an individual to actually believe no prior knowledge of the 1941 attack on Pearl Harbour? It was ‘fortunate’ in that on December 6th less than 15% of the American population favoured becoming involved in the ‘European’ war. On December 7th, the entire population favoured entering the war. Up until December 7th, America was ‘breaching’ neutrality guidelines as regards their equipment support for the allied army. Roosevelt was under extreme pressure from Winston Churchill to do his part in the war.
Look to Britain. Apart from an eight month period in 1943, the British were privy to all German communication courtesy of them breaking the Enigma code. Prior 1943 the Enigma machine was a three spool cipher machine which the Germans believed unable to crack. In 1943 the Germans designed the four-spool cipher with billions more combinations. A few months later the British also cracked this cipher. Basically, the British knew for the duration of the war most, if not all German planning, so could hardly not be aware of atrocities committed during the war nor be suprised by any German military action.
Hark back to the S.S. Lousitania in 1915. It was well known that American flagged ‘neutral’ passenger ships were transporting military equipment to Britain in contravention of neutrality agreements. The then lord of the Admiralty (the same Winston Churchill from memory) apparently ignored to inform the captain of the Lousitania of German U-boat activity close to shore. The result was a loss of around 1500 lives. Similarly, America was under extreme pressure to enter the ‘Great War’ but remained neutral until 1917.
In the world of politics there are no real secrets, only suppression of the truth. History in retrospect is generally kind to colonising super-powers. Look to the sinking of the American warship in San Salvador’ in around 1905. Approximately 15 American sailors were killed when the warship ‘peacefully’ at anchor in the harbour was rocked by an explosion. The U.S. declared war on Spain and within minutes had not only taken the carribean but the Phillipines as well. History would have us believe that this was an act of war by an unfriendly government and yet evidence suggests the explosion onboard the warship was linked more closely to home. Remember, that up until the late 1890s, America was more focussed internally, but with the rise of ‘teddy bear’ Roosevelt, America became a colonising super power.