Member Rara Avis
the ass-end of space
The following are excerpts I've personally taken from the NAVY COURT OF INQUIRY's REPORT: HEARINGS BEFORE THE JOINT COMITTEE ON THE INVESTIGATION OF THE PEARL HARBOR ATTACK dated 1946:
It is a matter of general knowledge that Japan has had for many years a thorough system of espionage throughout the world and continuously sought and received information regarding the location and movements of United States naval vessels. There were certain messages received in the Navy Department which showed very clearly that Japan, at this critical period, was particularly desirous of obtaining exact information from two sources, namely, Manila and Honolulu.
Messages between Tokyo, Manila, and Honolulu inquiring especially about planes, ships, their places of anchorage, etc., in the latter ports, were intercepted. Similar messages were sent to Japanese officials in Honolulu clearly indicating that Japan was most  desirous of obtaining exact information as to ships in Pearl Harbor.
The important messages having special reference to Pearl Harbor were as follows:
(a) On 15 November, 1941, Document 24, Exhibit 63, an intercept from Tokyo to Honolulu, translated in Navy Department, 3 December, 1941, states:
"As relations between Japan and the United States are most critical make your "ships in harbor report" irregular but at rate of twice a week. Although you already are no doubt aware, please take extra care to maintain secrecy."
(b) On 18 November, 1941, Document 37, Exhibit 63, an intercept from Tokyo to Honolulu, translated in Navy Department on 5 December, 1941, states:
"Please report on the following areas as to vessels anchored therein: Area "N" Pearl Harbor, Manila Bay, and areas adjacent thereto. Make your investigation with great secrecy."
Note by Navy Department on this message:
"Manila Bay" probably means "Mamala Bay."
(c) On 18 November, 1941, Document 40, Exhibit 63, an intercept from Honolulu to Tokyo and translated in Navy Department 6 December, 1941, gives information as to ships moored in certain areas in Pearl Harbor and movements of ships in and out.
 (d) On 29 November, 1941, Document 36, Exhibit 63, an intercept from Tokyo to Honolulu, translated in Washington 5 December, 1941, states:
"We have been receiving reports from you on ship movements but in future will you also report even where there are no movements."
The message which General Marshall sent to the Commanding General, Hawaiian Department (Exhibit 48) reads as follows:
"Japanese are presenting at one p.m. Eastern Standard Time today what amounts to an ultimatum also they are under orders to destroy their Code machine immediately stop Just what significance the hour set may have we do not know but be on alert accordingly stop Inform naval authorities of this communication."
This message left the War Department at 11:52 a.m., Washington time, was sent out over R.C.A. at 12:17 p.m. (6:47 a.m.Honolulu time) and arrived in Honolulu's R.C.A. office at 7:33 a.m. Honolulu time. There remained but 22 minutes before the attack for delivery, decoding, dissemination,
and action. Lieut. General Short did not receive the decoded dispatch until the afternoon of 7 December, several hours after the attacking force had departed.
Had the telephone and plain language been used, this message could have been received in Hawaii before the attack began.
Based on Findings XVIII and XIX, the Court is of the opinion that Admiral Harold R. Stark, U.S.N., Chief of Naval Operations and responsible for the operations of the Fleet, failed to display the sound judgment expected of him in that he did not transmit to Admiral Kimmel, Commander-in-Chief, Pacific fleet, during the very critical period 26 November to 7 December, important information which he had regarding the Japanese situation and, especially, in that, on the morning of 7 December, 1941, he did not transmit immediately  the fact that a message had been received which appeared to indicate that a break in diplomatic relations was imminent, and that an attack in the Hawaiian area might be expected soon
Now, in the end, the conclusion of the Joint Comittee was that while evidence indicated there was sufficient intelligence available to determine Pearl Harbor as the target of an impending attack, it was simply a case of faulty communication and bad judgement.
But thanks to the Freedom of Information Act, documents now reveal that numerous warnings were recieved by domestic and international intelligence communities indicating Pearl Harbor as a target. They were warned as early as January 1941 by their Japanese Ambassador but dismissed the information(also found in the Hearings).
Also discovered are various memos, diaries and documents indicating foreknowledge of an imminent attack. Decoded transmission intercepts are particularly damning.
I can't accept or condemn the strategy because FDR was obviously thin on options. It's an sad but common tactic of warfare.