Speech on Hypo by CAPT Biard
July, 12 2002

On 7 December, 1941, some 10 officers and about 30 enlisted men were serving in a highly secret operational intelligence group in the basement of the Administration Building in Pearl Harbor. This group was a fairly new unit — the newest of the U. S. Navy’s three World War II code-breaking stations. It had been placed in operation only seven months earlier — on 1 May 1941. The senior and oldest of the three stations was in Washington, D.C. [OP-20-G]. A second station was operating in the Philippines on the island of Corregidor in the entrance to Manila Bay.

Less than ten weeks earlier — on 30 September — four other young officers and I, all fresh from studying the Japanese language in Tokyo.

“Gentlemen, here are your desks. Start breaking Japanese codes.”

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CAPT Joseph Rochefort

Fortunately, my desk was next to Rochefort’s. People in the basement came to him with problems or just to discuss the day’s developments. By eavesdropping on these discussions I learned much… and quickly developed an undying respect for this brilliant, fast-thinking Rochefort.

During that first seven months of its existence the basement group had been assigned and was working on three Japanese naval codes and ciphers which, unfortunately, either yielded no really useful information when we could read them or which we could not break at all. The net result was that we detected absolutely no warning of the impending attack on Pearl Harbor. A broken – hearted Admiral Husband E. Kimmel, Commander in Chief of the U.S. Pacific Fleet on that 7 December, 1941, certainly had scant reason to thank our basement group for anything. But that was hardly our fault. Later, Admiral Chester W. Nimitz , who succeeded Admiral Kimmel, said of that same — well, almost the same — basement team:

“For several months after the outbreak of the war with Japan the very fate of our nation rested in the hands of a small group of very dedicated and highly devoted men working in the basement under the Administrative Building in Pearl Harbor.”

We, in that small group, had a more descriptive term for that unventilated enclosure in which we worked. We, more appropriately, called it “The Dungeon.”

Permit me to digress here to say that the code-breaking unit on Corregidor was evacuated to Australia in February through April of 1942 and was re-established in lovely Melbourne, where it operated for the remainder of the war. I was one of the very few World War II code breakers who served in all three of the Navy’s code breaking units and, I hasten to say, that Melbourne was a most wonderful place in which to enjoy the sweet revenge from breaking the enemy’s codes and ciphers.

I now return to the previous discussion. As Admiral Nimitz indicated in the remark just quoted, in a very few short weeks our small group changed from an essentially ineffective unit to one of the nation’s most important wartime assets. Without us there would have been no victory at Midway and the United States quite well might, by early 1943, have lost the war in both the Pacific and the Atlantic Oceans.

The story of just why and how that change occurred in our Dungeon unit has been partly – but only partly – told. The two authors who have written most knowingly about it knew us well, but not quite well enough. Since no one has told the full story – and only three persons alive today can fill in the blanks – I think it appropriate here to add a few remarks of my own.

First, by hindsight, I can say that four miracles blessed us in the Dungeon during that otherwise tragic December. Each of these four miracles was essential and absolutely necessary. Not until much later could we perceive just how very well we had been blessed.

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LCDR Joseph Finnegan

The first miracle was performed on 7 December. The Japanese bombed and badly damaged the battleship TENNESSEE causing it to settle to the bottom of Pearl Harbor. But in doing this they made one fatal mistake. They spared a very special one of her officers, a certain Lieutenant Commander Joseph Finnegan, U.S. Naval Academy Class of 1928, Tokyo-trained Japanese linguist, usually gregarious but sometimes reclusive, intuitive, brilliant, volatile, and a professional U.S. Irishman from Boston. The Japanese paid a high price for that mistake. It cost them the war.

I knew Joe well – very well – for years before he joined our Dungeon unit on that seventh of December.

The second December miracle occurred on 10 December, three days after the attack. Washington, on that date, gave the Dungeon permission to work on the Japanese Navy’s five digit, two-part, enciphered, widely used strategic code. This major code was given the U.S. Navy designation of JN-25. The Japanese Navy referred to it as Navy Codebook D. Washington and Corregidor had already made a meaningful dent in it, but progress following that dent had been painfully slow. The Dungeon soon would help to change that state.

The third December miracle – also unrecognized at the time came when the fairly junior Rear Admiral Chester W. Nimitz was ordered to take command of the badly battered U. S. Pacific Fleet. The miracle really was this. When we in the Dungeon produced our necessary miracle – or miracles – he stuck his neck out fifty feet and let his intelligence officer sell him what even Washington insisted was a very faulty bill of goods.

The fourth December miracle followed upon the third. It came as soon as Admiral Nimitz assumed command in the Pacific. He immediately told Admiral Kimmel’s nervous and fearful staff some words that gave them heart. All of them were to remain in their positions and work for him – as long as they continued to do their work well. With these words he retained as his intelligence officer Admiral Kimmel’s most junior section chief [Lieutenant] Commander Edwin T. Layton, U.S. Naval Academy Class of 1924, Japanese linguist, former code-breaker and intelligence operator extra-ordinary.

With these four miracles now working for us our Dungeon group was ready to start moving.

The fastest movers in the Dungeon were five in number. And Joe Finnegan was one of them. Without any one of these five we almost surely would have had no victory at Midway, the Japanese would have continued to roll on and on, and before we could have got our war machine together and in gear we would have lost the war in both the Pacific and the Atlantic. I wish there were time for me to expand on this more fully but here I want to emphasize that those on the Dungeon first team complemented one another almost perfectly — even miraculously. If any one — yes, any one of these five had not been with us from December, 1941 to June 1942 the history of World War II would now be different. The Dungeon group would have performed more slowly and less confidently; estimates of Japanese intentions and movements would have suffered; and the critical time table for Midway would have been produced too late — indeed, if it could have been produced at all. And that would have meant disaster.

The five leading miracle workers in that Dungeon crew are easy to name but far more difficult to describe. Top honors indisputably must go to our brilliant officer-in-charge, Commander Joseph J. Rochefort.

Source: http://www.usspennsylvania.com/TheDungeon.htm