[Retain Mike]

Revisionists offer arguments that FDR, Cordell Hull, and George Marshall foreknew the Pearl Harbor attack. These authors review historical events for those few data points that indicate an overwhelming attack. However, living history forward means accumulating and discerning patterns from 10,000’s of data points coming from humint, radio traffic analysis, code breaking, etc.

The Pearl Harbor attack astonished the administration and military professionals. Never before had even two carriers for any country planned and/or coordinated an attack on a naval or land target. No inkling existed in any allied Naval operational and intelligence community of a capability beyond the 21 bi-plane torpedo bombers from a single British carrier that attacked the Italian Navy at Taranto.

Yet, for Pearl Harbor the Japanese had forged a strategic weapon of six carriers with escorts and auxiliaries for a coordinated attack by 360 planes. The attack was not only unprecedented, but unexpected, because all preparations were conducted without recourse to the diplomatic Purple Code that U.S. codebreakers were reading in substantial portions. The U.S. had no agents in Japan and the Imperial Japanese Navy excluded the diplomatic corps from their plans.

To solve problems regarding bombing, torpedoes, and underway refueling the attack plan relied on oral doctrines and technical innovations developed during the last ninety days prior to deployment. Therefore, even reading the naval JN25 code vital for Midway would not have helped.

The attack was a truly unexpected and improbable use of the Japanese air fleet.

War Plan Orange
http://en.wikipedia.org/wiki/War_Plan_Orange
Naval History: Pearl Harbor’s Overlooked Answer
http://www.usni.org/magazines/navalhistory/2011-12/pearl-harbors-overlooked-answer

“And I Was There” by Rear Admiral Edwin T. Layton

At Dawn We Slept by Gordon W. Prange

[PieterCasparzen]

You need to look into the activities of financial elites and their operatives prior to the attack.

[CrazyIvan]

I have read At Dawn We Slept twice and will probably read it again some day. Quite possibly one of the best researched and unbiased works on an event ever written.

[Rockingham]

The potential for a Jap carrier attack on Pearl Harbor was well-recognized even though the precise plan and technical details remained open to improvisation. Journalists had long written of the risk of such an attack, US naval strategists had war-gamed it, and as the British demonstrated on the Italian fleet at Taranto, even obsolete biplanes from a single carrier could deliver a major blow to a fleet in a protected anchorage.

Call it revisionism, but Day Of Deceit: The Truth About FDR and Pearl Harbor, by Robert Stinnett, and Pearl Harbor: The Seeds and Fruits of Infamy, by Percy L. Greaves Jr. make a worthy case that FDR and his associates knew of the impending attack on Pearl Harbor. Most likely, they expected the attack to be easily repulsed, unaware of the combat strength of Japanese naval aviation and of the lack of defensive readiness at Pearl.

Although the extent and reason for the tactical surprise that Japan achieved at Pearl Harbor remain disputed, Japan's strength and daring clearly were a strategic surprise for the US -- a development that FDR and his associates must take the blame for. They underestimated Japan's potential as an adversary and the US paid heavily for that error.

Notably, with pertinent intelligence files in US and British archives still secret, the case for a revisionist view of the Pearl Harbor attack cannot be definitively rejected. Let us hope that we both live long enough to be around when those files are finally released to public view and the issues addressed on a more informed basis.