On 7 December 1941 Japanese aircraft attacked the headquarters of the US Pacific fleet at Pearl Harbor. Japan also invaded British and Dutch colonies on US-held islands across the Pacific. American president Franklin Delano Roosevelt told congress it was 'a date which will live in infamy', and condemned Japan for its 'surprise offensive' and 'unprovoked and dastardly attack'. To this day most people in America and Britain accept Roosevelt's characterisation of the Pearl Harbor attack as an unprovoked surprise assault which dragged an unwilling USA into the Second World War. Governments on both sides of the Atlantic have done their best to suppress any information which might suggest otherwise.
Many important papers relating to the attack are still secret.
A British book on the subject was banned by the government's D-notice committee in 1989. Winston Churchill's papers for the period are not to be released to the public until 2016. But a cursory examination of the available evidence which is available shows that the truth is very different from the school book history. For a start, both American and British cryptographers had broken Japan's most secret communications codes. They often decoded and read diplomatic or military messages before their Japanese counterparts.