President Roosevelt (FDR) provoked the attack, knew about it in advance and covered up his failure to warn the Hawaiian commanders. FDR needed the attack to sucker Hitler to declare war, since the public and Congress were overwhelmingly against entering the war in Europe. It was his backdoor to war.
FDR blinded the commanders at Pearl Harbor and set them up by -
1. denying intelligence to Hawaii (HI)
2. on Nov 27, misleading the commanders into thinking negotiations with Japan were continuing to prevent them from realizing the war was on
3. having false information sent to HI about the location of the Japanese carrier fleet.
GREAT MOMENTS IN THE HISTORY OF THE FBI.
"[Your information is] too precise, too complete to be believed. The questionnaire plus the other information you brought spell out in detail exactly where, when, how, and by whom we are to be attacked. If anything, it sounds like a trap."
FBI response to the top British spy, Dusko Popov (code named "Tricycle") on August 10, 1941, dismissing Popov's report of the complete Japanese plan for the attack on Pearl Harbor.
Pearl Harbor: The Verdict Of History by Gordon Prange, appendix 7 published in 1986. Based on records from the JOINT CONGRESSIONAL COMMITTEE on the Investigation of the Pearl Harbor Attack, Nov 15, 1945 to May 31, 1946.