Pearl Harbor Advance-knowledge Conspiracy Theory - Official U.S. War Warnings

Official U.S. War Warnings

In late November 1941, both the U.S. Navy and Army sent explicit war with Japan warnings to all Pacific commands. Although these plainly stated the high probability of imminent war with Japan, and instructed recipients to be accordingly on alert for war, they did not mention the likelihood of an attack on Pearl Harbor itself, instead focusing on the Far East. Washington forwarded none of the raw intelligence it had, and little of its intelligence estimates (after analysis), to Hawaiian commanders, Admiral Husband E. Kimmel and General Walter C. Short. Washington did not solicit their views about likelihood of war or Hawaiian special concerns. Washington's war warning messages have also been criticised by some (e.g., the U.S. Army Pearl Harbor Board - "Do/Don't Messages") as containing "conflicting and imprecise" language.

Since the Army was officially responsible for the security of the Pearl Harbor facilities and Hawaiian defense generally, and so of the Navy's ships while in port, Army actions are of particular interest. Short reported to Washington he had increased his alert level (but his earlier change in meaning for those levels was not understood in Washington and led to misunderstanding there about what he was really doing). In addition, Short's main concern was sabotage from fifth columnists (expected to precede the outbreak of war for decades preceding the attack), which accounts for his orders that Army Air Corps planes be parked close together near the center of the airfields. There seems to have been no increased Army urgency about getting its existing radar equipment properly integrated with the local command and control in the year it had been available and operational in Hawaii before the attack. Leisurely radar training continued and the recently organized early warning center was left minimally staffed. Anti-aircraft guns remained in a state of low readiness, with ammunition in secured lockers. Neither Army long range bombers nor Navy PBYs were used effectively, remaining on a peacetime maintenance and use schedule. Short evidently failed to understand he had the responsibility to defend the fleet. In Short's defense, it should be noted he had training responsibilities to meet, and the best patrol aircraft, B-17s and B-24s, were in demand in the Philippines and Britain, both of which had higher priority.

Little was done to prepare for air attack. Inter-service rivalries between Kimmel and Short did not improve the situation. Particularly, most intelligence information was sent to Kimmel, assuming he would relay it to Short, and vice versa; this assumption was honored mostly in the breach. Hawaii did not have a Purple cipher machine (although, by agreement at the highest levels between U.S. and UK cryptographic establishments, four had been delivered to the British by October 1941), so Hawaii remained dependent on Washington for intelligence from that (militarily limited) source. However, since Short had no liaison with Kimmel's intelligence staff, he was usually left out of the loop. Henry Clausen reported the war warnings could not be more precise because Washington could not risk Japan guessing the U.S. was reading important parts of their traffic (i.e., most importantly Purple, despite the fact there was no known tactical or strategic info in that traffic), as well as the fact neither was cleared to receive Purple; Clausen does not answer why Washington could not have said "an exceptionally reliable source" was involved, with very strong instructions to pay attention.

Additionally, Clausen claims military men of Kimmel and Short's seniority and background should have understood the significance of the warnings, and should have been more vigilant than they were, as for instance in scouting plane flights from Hawaii, which were partial at best in the period just before the attack. All other Pacific commands took appropriate measures for their situations.

Like most commentators, Clausen ignores what the "war warnings" (and their context) explicitly warn, though indistinctly, against. Washington, with more complete intelligence than any field command, expected an attack anywhere on a list of possible locations (Pearl Harbor not among them), and since the Japanese were already committed to Thailand, it seems to have been expected another major operation by them was impossible. Clausen, like most, also ignores what actions Kimmel, Short, and Admiral Claude C. Bloch (Commander, Fourteenth Naval District, responsible for naval facilities in Hawaii) actually took. They took precautions against sabotage, widely expected as a precursor to war, and reported their preparations. The Hawaii commanders did not anticipate an air attack; no one did so explicitly. Indeed, the prevailing view at the time was Japan could not execute two major naval operations at once, so with the Thailand invasion convoy known to be at sea, the Hawaii commanders had good reason to feel safe.

One major point often omitted from the debate (though Costello covers it thoroughly) is the Philippines, where MacArthur, unlike Kimmel or Short, had complete access to all decrypted Purple and JN-25 traffic could provide (indeed, Stinnet quotes Whitlock to that effect), and was nonetheless caught unprepared and with all planes on the ground nevertheless, nine hours after the Pearl Harbor attack. Caidin and Blair also raise the issue.

Although it has been argued that there was sufficient intelligence at the time to give commanders at Pearl Harbor a greater level of alert, some factors may take on unambiguous meaning not clear at the time, lost in what Roberta Wohlstetter in her masterful examination of the situation called "noise", "scattered amid the dross of many thousands of other intelligence bits, some of which just as convincingly pointed to a Japanese attack on the Panama Canal."