The Pearl Harbor advance-knowledge debate is a dispute over what, if any, advance knowledge American officials had of Japan's December 7, 1941 attack on Pearl Harbor.
Ever since the Japanese attack there has been debate as to how and why the United States had been caught unaware, and how much and when American officials knew of Japanese plans and related topics. Several writers, including journalist Robert Stinnett and former United States rear admiral Robert Alfred Theobald, have argued that various parties high in the US and British governments knew of the attack in advance and may even have let it happen or encouraged it in order to force America into war via the "back door." Evidence supporting this view is taken from quotations and source documents from the time and the release of newer materials.
Examination of information released since the War has revealed there was considerable intelligence information available to US and other nations' officials. It may have been the failure to process and use this information effectively that has led some to invoke conspiracy theories rather than a less interesting mix of mistake and circumstance.