This Is our Village

Sunday, December 5, 2010


Morotai Beach landing zone
U.S. forces landed on the island of Morotai in mid-September 1944, with the objective of establishing facilities for air campaigns against the Japanese-held Philippines. Morotai is in the north of the chain of islands then known as the Netherlands East Indies (today, Indonesia), and was well positioned for air strikes against the Philippine island of Mindanao.

The photograph shows one of the Morotai beaches where U.S. forces landed.

As the landings unfolded, SIGINT developed by Central Bureau Brisbane (CBB) gave U.S. commanders detailed insight into Japanese strength and plans. CBB was the cryptologic organization established to support Allied operations in the Southwest Pacific Theater and had cryptologic personnel from all the Allied nations involved in the Theater.

Although the Japanese military had not detected the destination or timing of the initial landings, the decrypt of a Japanese message in early November indicated that Japanese headquarters in the Philippines now recognized the threat presented by Allied operations on Morotai and was deploying troops to meet it. Decrypts over the next few days revealed the landing of a Japanese infantry regiment and gave total Japanese strength on the island as 1,900 men.

Although decrypts with specifics about Japanese air raids on American air fields on Morotai in November and December came after the attacks, the U.S. defenders had been forewarned of the attacks by tactical intercept and traffic analysis.
Decrypts of messages relating to Japanese attempts to outrun the American air and naval blockade around Morotai revealed the location of a Japanese military “hideout.” U.S. bombers subsequently attacked and eliminated the Japanese base.
An Army history of the Morotai operation notes that the airfields established there proved extremely valuable in subsequent operations.

SIGINT produced by CBB proved of inestimable value in saving American lives and successful conclusion of the military operations.
Dave Israel


  1. OK no more hints Dave, we will get you Giorgio Armani Code manly parfum for the holidays.

  2. Code-breaking has always fascinated me. Years ago I read a couple of books written about British/US code-breaking during World War 2. One was about "Enigma" and had to do with the European theater of operations, I think. I remember reading that Britain and the US had to be very careful to not tip off the Germans that we HAD broken the code; otherwise, its use thereafter would be nil. This meant sacrificing the small fish in order to catch the big fish, and it meant loss of some allied lives in order to keep our knowledge of the code secret. The other book was about a code with a similar name, I think: Ultra , Omega, Purple or some such thing.

    Could you recommend a couple of books on the subject, Dave? Layperson books, I mean, without too much of the technical. I'll get them from the library sometime.


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