You need to look into the activities of financial elites and their operatives prior to the attack.
This limited discussion of the Pearl Harbor conspiracy theorists covered only the likelihood the attack would be considered probable and/or of such a scale. Gordon W. Prange in writing At Dawn We Slept presented arguably the most scholarly, well researched volume on the attack from both the Japanese and American perspectives. The book ends with an eleven page summary refuting a host of revisionist imaginings including internal political collusion, secret treaties and international intrigues.