Customer Reviews

The Emperor's Codes: The Breaking of Japan's Secret Ciphers

5 star:		(2)
4 star:		(5)
3 star:		(3)
2 star:		(4)
1 star:		(2)

 

 

I recommend buying Emperor's Codes. However, it is just
a small part of the history and has some significant flaws.

Michael Smith's book failed to convince me that the British
were the primary breakers of most Japanese codes and ciphers
before and during the war. Both the British and American invested
increasing resources to identify and break Japanese codes.
The efforts of both were separate, but as the war continued
agreements were worked out to share the results of their
individual work. Some of these efforts were impeded by
politics on both sides. The United States was not the sole
obstructor of efforts to share intelligence. Both sides also
made mistakes in ignoring intelligence from their codebreakers.
Smith's arguments come across as rather one-sided and sound
a bit too resentful for good history in my opinion. He would
have been better off detailing the British and Australian
efforts and let that speak for itself.

He greatly misleads the readers by implying that the breaking
of JN25, the main Japanese Naval Operational Code, by Colonel
Tiltman of GC&CS was a prime British triumph, and that
later codebreaking efforts by Americans to break JN25 was
mere catch up with the British. The fact is JN25A was broken
by Tiltman but not the successor JN25B. JN25B superceeded
JN25A and was a completely new code that was vastly more
complex than JN25A. It was related to JN25A in name only.
The British did not break JN25B. Joe Rochefort and his group

in Hawaii successfully discovered or guessed at enough code
groups to predict the Japanese invasion attempt on Midway, the
greatest code triumph of the war in the Pacific.

One thing I did like about this book was the identification of
the various codes and their purposes. Amongst those id'd
are JN11 (Fleet Auxillary Code), JN40 Naval Shipping Code,
ZMTW or 2468 (Army Shipping Code), JN152 (Navigational Warning
Code), JMA - Coral, etc. So many writers of the Pacific War
refer to the breaking of the 'Japanese Code'. Well, there was
not a single code but many different codes and ciphers with many
different uses. A code as minor as a contact report code used
by the merchant shipping was extremely helpful in identifying
the location of convoys. For this information alone I was happy
to have bought the book.

There is no question that the British and Australians contributed
to the codebreaking efforts in the Pacific. Especially when the
sharing of information enhanced everybody's efforts. For their
efforts I am surely grateful. It saved many lives.

I believe a good history remains to be written that identifies
the various codes, describes the cryptanalysis, the
intelligence value, and how the information was used for each
code. Until that time interested readers must cull through the
various books and piece together the story. I recommend reading
John Prados's 'Combined Fleet Decoded', Edward Drea's
'MacArthur's Ultra', Stripp's 'Codebreakers of the Far East',
and Edwin Layton's 'I Was There'.

The history of cracking the German codes during World War II has emerged slowly over the last ten years, and is now fairly fully described. By comparison, relatively little has been revealed about the comparable efforts aimed at Japanese codes. Recent declassification of British documents, privileged access to secret Australian histories of these events, and extensive new interviews with participants by Mr. Michael Smith (who spent 9 years in codebreaking for British Intelligence) provide the basis for the most complete and interesting account yet of the efforts aimed at Japan. The book is a success as a riveting history of individuals, for explaining the techniques involved, changing your view of how the war was won, and for raising fascinating new questions about military activities (did the atomic bomb really have to be dropped, or did Truman drop the ball?).

Right after World War II, the American cryptographers broke the story of how they had cracked the Japanese diplomatic code (the so-called Purple code). What was not known, until recently, is that almost all of success with the other Japanese codes involved British and/or Australian codebreakers. Even more surprising is that the U.S. Navy kept intercepts and code books from the British codebreakers despite agreements to share. Undoubtedly, many lost their lives and the war was prolonged because of these U.S. errors.

But there were also errors in using the coded output. Some commanders just wouldn't take it seriously, and placed their ships in harm's way. Consider the irony of the British decoding an impending attack on their codebreaking home in Ceylon which the British Navy largely ignored after the attack was delayed for a few days.

The Japanese codebreaking was much more difficult than that for the German codes because the allies had few Japanese readers to draw on. Before the war's end, the British invented a six month cram course that effectively taught code-breaking Japanese. Also, because the British lost so many bases in Asia, the codebreakers were pushed further and further away from Japanese bases and shipping. That meant an inability to get enough radio messages to be able to effectively decode. At the key turning points in the war, the British were trying to listen to Japan from a lousy station in Kenya. Go figure! Here's where the U.S. Navy could have made a big difference, because they always had lots of intercepts from naval shipping in the Pacific. "The record of the US Navy in cooperation, not just with the British but with their own Army, was not merely lamentable, it was shameful."

Interestingly, the Japanese codes were able to be broken mostly because the Japanese assumed that no one could. So when it appeared that the codes might have been compromised, they kept using the same ones. That gave the allies an edge. The Japanese also had some habits that helped. They began many messages with similar flowery language such as "I have the honour to inform your excellency . . . ." Find enough of those messages, and you could begin to decode.

It was fascinating to see how one source of intelligence helped other parts of the war. The Japanese ambassador in Berlin was a great source of information about Nazi Germany, through the broken Purple code. He toured Normandy just before D-Day, and his rambling account tipped the allies off to the need to throw Hitler's attention towards Pas de Calais.

The book also recounts how a broken message allowed the allies to shoot down Admiral Yamamoto. You also get a very fine explanation of how the coded messages were used to help win the Battle of Midway and the speed the liberation of the Philippines.

Long sections of the story are presented as quoted material from partipants, which provides a change in voice and of perspective. Many of the codebreakers in the various Asian locations were women. What was it like to find a giant snake in the toilet that you so desperately wanted to use? Many of those involved in codebreaking married, and had to deal with the many British retreats (from Hong Kong to Singapore to Colombo to Mombasa). Their stories will make all of this much more appealing and personal to you.

After you finish understanding how valuable it is to understand your opponent, think about your competitors in work or play activities. How well have you undertaken to understand what they are thinking about in order to anticipate what they will do next? For those you serve, don't forget that you can ask them directly.

Get to the bottom of important puzzles!

Michael Smith's book is a wonderful addition to the growing list of books dealing with code breaking during the Second World War. I was less then familar with the breaking of the Japanese codes, so I picked up this book to educate myself about an unfamilar subject. Smith's book provided a great overview of British attempts to break the Japanese codes during the war. This is not a book dealing with all of code breaking, its primary focus is on the British role. Smith's assertion is that British codebreakers did as much as Americans in breaking the Japanese codes. Not a difficult argument to imagine from an Englishman who spent a number of years working in codebreaking. Smith obviously has a bias toward the British codebreakers who came before him. That aside, the book provides wonderful detail and a number of quotes from people who were actually involved. The personal stories help bring the war to life. Occasionally it become very technical about how the codebreaking was done but all in all a good read.

Admittedly Michael Smith does have two important agendas in his book "The Emperor's Codes"; first to tell the largely untold saga of breaking Japanese military and diplomatic codes, and then, to emphasize the important role played by British codebreakers in unlocking these Japanese secrets. On both accounts, Smith succeeds admirably, even if he tends to dwell too much on the anecdotal first hand accounts given by some codebreakers. Smith notes that many of the most important Japanese codes were broken first by Australian and British codebreakers such as Eric Nave and John Tiltman, long before American codebreakers made significant headway in reading encrypted Japanese messages. However, he does not trivialize the important contributions American codebreakers made in this effort, though some readers may wish that Smith gave a more comprehensive overview of American achievements in codebreaking, which would prove to be far more substantial by the war's end. Nevertheless, Michael Smith has made an important contribution in emphasizing the important work done by codebreakers during the Pacific theater of World War Two, which unfortunately has been long overlooked in stark contrast to the well documented history of cracking Enigma and other Nazi codes by both British and American codebreakers.

This is an interesting and journalistic account of Allied efforts to break Japanese codes during WWII. There has been a great deal published about Allied, mainly British, success in deciphering German codes but little on the corresponding effort aimed at Japan. Smith provides a broad outline of the Allied effort to attack Japanese codes. He is especially interested in documenting the British role in this effort. This emphasis occurs for two reasons. First, he is especially concerned with dispeliing the notion that American cryptographers completely dominated this effort. Second, most of his sources are British, due partly to the greater availability of relevant British and Australian sources. The book does an adequate job of covering the major efforts in cryptography, discusses the major figures, and some of the problems inherent in this collaboration between the allies. The American Navy appears as having a poor record of interservice and inter-Ally cooperation. This book has some deficiencies. It is not really detailed or systematic enough. While Smith's emphasis on the British is understandable, I don't think there is enough material on American efforts to give a truly balanced picture. Much of the material is presented in an anecdotal manner, punctuated with interviews of participants. These excerpts are interesting, well chosen, and entertaining but there is not much corresponding analysis. For example, there is enough in the book on details of cryptography to make the reader confused but not enough to make the subject readily understandable. Smith also deals poorly with the scope of Allied efforts. Implicit in the book is the growth of cryptography and signal intelligence from a rudimentary prewar effort to a major and very well organized enterprise. Yet, there is no systematic accounting of the growth and organization of these complex efforts. This subject really deserves a more systematic and detailed treatment.

This book is way too biased. Tha book reads as though, the British did everything, the Americans took the credit. The British are good codebreakers, but a better balance of historical facts would have been good.

I'm an admitted technology geek. I have read stuff over the years about the breaking of Enigma, I visited the Deutsches Museum in Munich and saw Enigma machines. I recently read the fictional CRYPTONOMICON and figured a dose of history on the subject would be good.

First of all: there is a huge difference between a large collection of "facts" and a readable story or a readable "history" (if you don't believe me, contrast the Christian Biblical "Book of Genesis" with the "Book of Numbers").

It is clear this author has an axe to grind - I wonder if the title was his first choice or if the title was changed by the publisher?

The author believes that the Brits deserve more credit and that the Americans were scoundrels and the two sides couldn't play together.

Rather than offering anecdotes of what a particular 18 year old WREN thought of the foibles of her commanding officer, it would have been enlightening to get some sense of the urgencies and priorities and consequences of this little talked about war time effort.

The book recounts lots of personal minutia - if you're looking for any thing of substance, look elsewhere.

Not an easy read, unless you're already into ciphers, but a very useful exposition of the trials and tribulations of codebreaking in a wartime setting.

I'm amused that folks found it one-sided or biased. Hey, it's about the British effort, which was considerable! I thought Smith was more than fair to the American effort, which he concedes was larger and often faster. The point is: it took both British and American expertise (and contrasting attitudes) to do the job.

The most valuable lesson here is that the codes (neither German nor Japanese) were never entirely broken. The codebreaker's job was almost as arduous in August 1945 as it was in November 1941. How they did their work is endlessly fascinating.

Having read a number of books on the breaking of the german codes, I was hooked when I ran across this book. I like the detail and enjoyed the personal notes of many of the participants. However, it was the continual antagonism towards the U.S. code breaking effort that made it an effort instead of a joy to finish this book.

I was not happy reading this book.Book breaks no new ground.Author's attempt has been to show the British never lagged behind Americans in penetrating Japanese ciphers.Smith goes to extraordinary lengths to show how understanding was forged among Allies to share special intelligence.However Americans were intially unwilling to share intelligence with their British counterparts.Perhaps the former wanted to corner all military glory.I believe the principal credit for breaking Japanese codes must go cryptanalysts of US Navy.

Following the intricacies of Japanese codes have been a daunting task for me.I feel author ought to have explained this with diagrams or sketches which would have simplified the subject for a lay man like me.Precisely this is what Simon Singh has done in his path breaking work 'Code Book'.Book contains character profiles of leading British code breakers who served in the Far Eastern theatre of war.Author sidetracks a lot giving florid accounts of their personal lives.I found this very dragging.

However there is some interesting information .Nazi leader had a hunch that Normandy would be the site for D day landings although evidence pointed to Pas de Calais.This was known because Anglo-Amercans were reading messages sent Japanese ambassador in Berlin to Foreign office in Tokyo.This fore knowledge helped Allies to fine tune their deception.Other pertains to atomic bombing of Hiroshima and Nagasaki.Potsdam declaration by the big Three told Japan to surrender unconditionally.Japan was willing provided Anglo-Americans were willing to respect Emperor's status.Latter accepted this demand Still nuclear bombs were dropped .Why? Author justifiably expresses shock and surprise at this Allied decision.The incident has continued to baffle me to this day.Is Truman and Churchill guilty of perpetrating mass murder?