Admiral Fifty-six Yamamoto raised his binoculars and stood in the command tower with a blank face and looked out. At this time, the adjutant of staff came to report that Chinese planes were attacking the aircraft carrier "Zuihe".

"Boom!"

A Chinese attack plane hit by antiaircraft artillery fire swooped down with a long black smoke and crashed straight into the side of the "Yamato," exploding into a huge ball of fire.

Debris from the explosion flew in all directions, and some of the debris actually splashed onto the bridge.

The shock wave generated by the huge explosion shook the huge hull of the "Yamato" heavily, and when we saw that two antiaircraft gun emplacements had been destroyed, the gunners of the brigade were either killed or wounded, and some of the officers were distracted.

Yamamoto Fifty-six held a telescope and looked in the direction of the aircraft carrier squadron, and in the telescope, he could only see thick smoke billowing on the sea, and columns of smoke from countless shells exploding seemed to cover the sky like dark clouds. Hordes of Chinese planes whizzed through the air, and then continued to dive and drop bombs, throw torpedoes, and bomb and strafe at the attackers. All kinds of guns on this warship were firing fiercely, and the huge hull of an aircraft carrier was constantly shaking in the sea. Yamamoto 56 saw the shells fired by the warship erect a wall of steel fire in front of the enemy's attack.

Yamamoto lowered the telescope in his hand heavily. The Chinese's determination to fight, the resoluteness of their will to attack, and the ferocity of their offensive have left an indelible impression on his mind.

"The reconnaissance aircraft reported that the Chinese fleet had left the sea off Nagasaki and headed for the southeast." The staff officer came to report again.

"They're trying to escape!" The grass deer chief of staff said loudly.

Yamamoto Fifty-six turned around and came to the chart table, looking at the positions of the two fleets above, and the wrinkles on his face deepened.

"There are also possible surnames that lure enemies." Black Island Turtle Osa suddenly said.

"What do you say? Kuroshima-kun? Yamamoto Fifty-six turned his head to look at Kuroshima Kameto and asked, "Lure the enemy?" ”

"Yes. Your Excellency the Commander-in-Chief. Kuroshima Kameto replied in an affirmative tone, "The Shina fleet has stayed in the sea off Nagasaki for a long time, and the purpose seems to be to destroy the will of the imperial subjects in this way, challenge the imperial navy, and conduct a decisive battle with the main force of the imperial navy, but now that the main force of the imperial navy has been dispatched, the china fleet has actually chosen to retreat, and its intention is obvious, that is, to attract the main force of the imperial navy into the ambush circle, and they intend to use this method to destroy the main force of the imperial navy." ”

After listening to the analysis of the Kuroshima Kametoshi of "Akiyama Shinno's Second", Chief of Staff Kusaka couldn't help but gasp. But Yamamoto Isoroku was still very calm.

"In other words, there is still a Chinese attack fleet that responds." Yamamoto said.

Kuroshima Kameto continued, "Because according to the report of the reconnaissance plane, although the Shina Navy dispatched the main force this time, it was not all of it. Moreover, the whereabouts of the China Navy in the port of Truk are currently unknown, which also shows what the purpose of the China people is. ”

"In any case, this is also a real decisive battle that will determine the future fate of the Empire." Yamamoto Fifty-six pondered for a moment and said, "This time, we must go all out!" ”

"Order Hawaii's Third Fleet to set off immediately!"

Hearing Yamamoto's order, the communications officers immediately began to get busy.

While he was busy issuing radio commands, the United States, far away on the other side of the ocean, was also paying close attention to this naval battle of unprecedented scale.

Although 1943 was no longer the year of successive military defeats for the Allies. Churchill's "cascade of disasters" did not spread in the Far East, but the bombing of Yanjing himself dealt a major blow to the will of the Allies for a short time, but the subsequent massive retaliatory bombing of Tokyo by the Chinese lifted the spirits of the Americans. The U.S. Joint Chiefs of Staff considered the operation to be nothing more than an attack for propaganda purposes. It turns out they were all wrong. In the months that followed, this retaliatory attack on an unprecedented scale set off a chain of events through which the United States found an opportunity to contain the wave of conquest.

After the Chinese Air Force bombed Tokyo and caused great damage, the Navy reacted excessively by sending almost all the warships of the Combined Fleet. This generated a flood of radio signals that provided the U.S. Navy with an opportunity to win an unexpected, but crucial, secret victory. Although they do not yet have a naval force to rival their own, they have a huge advantage in covert electronic warfare, which is the key to gaining tactical superiority in the vast Pacific theater. This intelligence provided important clues to the Americans revealed to the Americans how the "Victory Disease" prompted the Victory Sickness to support too many battles on too long fronts, thus distracting them from their overwhelming advantage. Knowing in advance the weakness of the enemy's strategy, Admiral Nimitz was able to concentrate his limited naval forces against the enemy's actions one by one, thus disrupting his attempts to move south and west into the Pacific.

The frenzied pursuit of Chu Yangwei's retreating Chinese Navy's main fleet has added a lot of material to the intelligence puzzle, which the United States is painstakingly putting together in order to uncover the secrets of the second phase of the operation. From Alaska to Australia, the listeners of a series of radio stations around the Pacific Ocean, receiving a stream of coded telegrams from the air, which were then sent by teletyping telegraph to the Admiralty Intelligence Service in Washington for Lawrence? Codebreaker for Lieutenant Commander Sufford, or issued to Joseph Anderson, who worked at San Diego Naval Harbor? The smaller Pacific Fleet Operational Intelligence Service led by Rear Admiral Rocherford.

Since the beginning of the war, they have painstakingly deciphered the five-digit set of the Navy's main operational code, which is known as the "Navy's 25" (JN25). In addition to regular communications, they also use a particularly secure "comb" signal wavelength so that naval intelligence in San Diego, Brisbane, and Washington can exchange intercepted information with each other as they explore the pattern of telegraphs. It's a process that requires a decipherment team, a complex filing system, and an easy-to-use skill and intuition on IBM punch card tabulation machines. The clues to deciphering a set of codes are to be explored from the similarities and recurring forms of the two-letter code of place names, the time code, the call signal of the ship and the commander, and the same "handwriting" of the sender of the Morse code. The information was recorded on loose-leaf sheets, five inches long and eight inches wide, stacked in open boxes for backup, which the Pacific Fleet Operational Intelligence Service called "cards." The U.S. Navy shot down a reconnaissance plane at sea, and the documents recovered from the plane included air codes and ship call signal codes, which provided the first important clues.

The actual process of deciphering the coded telegram was a very difficult task, which required the ingenuity of man and the constant exploration of the International Business Machines tabulators. It is said that the Navy's No. 25 code is different from the diplomatic code translated by the machine that was deciphered by the "black box". It is a traditional cipher generated from two codebooks. The first "dictionary" is a random five-digit set of numbers, such as 4375265739142688822173923, which has a total of 45,000 numbers. Each group represents a specific word or phrase in the text. Before the coded telegram was sent, each set of numbers was added one after the other in a similar five-digit set of numbers in the second codebook. Each set of numbers is divisible by three in order to check for tampering, and therefore, their total number is also divisible by three. Before sending a telegram in Morse code, an index is placed in front of the telegram, and the recipient finds out which page, column, and line of the second codebook according to the index, and then translates the coded telegram with reference to the "dictionary".

For the codebreakers of the Admiralty Intelligence Service in Washington and the Pacific Fleet Operational Intelligence Service at Pearl Harbor, the large number of telegrams intercepted during the Chinese fleet's attack on the port of Nagasaki and the pursuit of the Chinese fleet by the Ship fleet was a great gain. Not only did the secret call signal tell them that almost every warship in Yamamoto's combined fleet had gone to sea, but the purpose of this massive operation was also exposed, and valuable insights clarified the meaning of many five-figure figures. During the five months that American cryptanalysts insisted on using the Type "B" cipher, they compiled the "dictionary" of the Navy No. 25 ciphers, adding many words. In order to maintain secrecy, the Naval Staff Headquarters in Tokyo had planned to replace the two codebooks on 1 November. However, they were convinced that their two-tiered cipher could not be deciphered by others, so they once again committed the "victory disease" and postponed the replacement to December 1, and later to January 1 of the following year, because it was very troublesome to send the new "dictionary" to every warship. As a result, the US Navy's intelligence agencies were so familiar with the ciphers of the Navy's Type 25B Fleet that they were able to decipher one-twentieth of all coded telegrams received each day. This information, combined with information gleaned from coded telegrams, which were relatively easy to decipher, began to paint a clear picture of the enemy's disposition and intentions. On October 25, a telegram referring to the RZP campaign implied that MO was referring to Port Moresby at the southern tip of New Guinea and RZQ was referring to a nearby seaplane base. This information was corroborated by important clues obtained after deciphering a telegram sent a week after the Chinese attack on Tokyo, requesting 1,000 documents to be used in the attack plan and a complete map of Australia. A telegram deciphered three days later clearly reads: "The goal of the MO is, first of all, to limit the activities of the enemy's fleet, which will be achieved by launching an offensive along the northern coast of Australia." "During the month, the number of telegrams increased, indicating that he was stepping up the build-up of planes, ships, and troops in preparation for a southward attack on Australia.

In the process of filling in the missing pieces of the intelligence patchwork by educated guesses, and by deciphering the code to make such an explanation, Joseph? Rocherford played a leading role. Rocherford has a superhuman memory for details, and has accumulated a wealth of knowledge and strong intuitive ability in the course of studying and studying naval operations for many years. He was the head and inspiration to eight hand-picked codebreakers in the Pacific Fleet's Operational Intelligence Service at Pearl Harbor. This intelligence unit has gradually acquired a special skill in deciphering the codes of the fleet. Their unique abilities earned Nimitz's trust, and he increasingly relied on their intelligence, which he used as his secret weapon in the most critical operational phase of the Pacific War.

"You don't need to be whimsical - but whims can help you." It was a warning posted on the wall opposite Rear Admiral Dwyer's desk, which was often littered with a jumble of drafts, intercepted telegrams, and tabulator prints. Rocherford's main assistant had a neat mustache, gold-rimmed glasses, and the eccentric demeanor of an absent-minded math professor. The Chief of Intelligence's penchant for wearing a pair of slippers and a faded crimson velvet smoking suit at work is a prime example. "Isolated like a submarine." "Here, the clock moment has lost any meaning, and the constant temperature in the air-conditioned environment has given rise to the joke that the only fresh air is brought in by the guests' pockets," said one BFIPU member, recalling their intense work day and night in the windowless basement of the new administrative building in the Port of San Diego, under the blinding lights, and under the constant beating of tabulators and telegraphs. The number of guests was very small, as there were armed guards standing guard in front of the single door with the sign of 'Operational Information Service'. ”

During these critical weeks of 1943, Dwyer and Rocherford were on duty 24 hours a day. Rocherford often spends days in the basement, struggling on sandwiches and coffee, sleeping on canvas beds between watchmakers. Here, both man and machine work in a highly centralized manner that can only be compared to the codebreakers of the Admiralty Intelligence Service and MacArthur Command in Washington. MacArthur's intelligence service was codenamed "Custer", and they renamed it "Bel Connan" after establishing a new headquarters in Australia.

The joint work of these three units has enabled the remnants of the Pacific Fleet to strike at these targets with the help of intercepted reports on the weather over the target areas. Radio intelligence also helped the small fleet blow up Frigate Reef (the reef between Hawaii and Midway), where the U.S. Navy had discovered that an enemy supply ship had refueled a seacraft attacking Oahu.

The Pacific Fleet Intelligence Department had a comprehensive grasp of the Navy's movements on the basis of information provided by Rocherford's Operational Intelligence Service. The Ministry of Intelligence was founded by Edwin? When Nimitz took over command under Leyton's leadership, he retained the promising young officer, appreciating his ability to often detect the enemy's next move. Leiden collects this information in every "Fact Sheet" and sends it to all ships and bases in code. Leiden's analysis of intelligence was based not only on deciphered codes, but also on a large amount of raw radio information, as well as on the experience he had gained while on duty in the Far East, which gave him a unique ability to see the Pacific Ocean from his own eyes.

More than a month before the Chinese Air Force's strategic bomber group set out to attack Tokyo, Leiden and his staff gathered the scattered intelligence provided by the intercepted signals, and foresaw the Navy's offensive against the Bismarck Islands and New Guinea a few days before the Imperial Naval Command issued the first operational orders. Obviously, his intention was to deploy several aircraft carriers, the South China Sea Army Division, and the 25th Air Force to launch a large-scale offensive. "I am now able to attack Port Moresby and Tulagi at the same time." The Pacific Fleet operational chronicle of that day reads. Three weeks later, the Admiralty Intelligence Service in Washington deciphered an order sent to Vice Admiral Inoue Nari, commander of the Fourth Fleet, to let the Americans know that as soon as the two aircraft carriers sent by the Nagumo Assault Fleet returning from the Indian Ocean arrived, they would begin to carry out the MO operation plan as soon as they arrived.

But what happened next prompted him to change his battle plan, and after the Chinese Air Force bombed Tokyo with incendiary bombs and caused heavy casualties among his soldiers and civilians, he realized how weak their defenses on home were and how easily the Chinese could cause great damage. After the Chinese Air Force bombed the mainland, the Chinese navy also began to make frequent sorties, and the military command of the navy judged that the Chinese navy might launch an attack on the mainland, so it began to gather naval forces on the mainland to prepare for a decisive battle with the Chinese navy. In this way, the plan to go south was naturally canceled.

The cancellation of the plan to advance southward was a great relief to both the Americans and the British. As Australia turned the corner, Curtin and Churchill's once-strained relationship over the deployment of troops eased. In Churchill's view, "the war in the Pacific turned into a war between the yellow race." But Roosevelt did not see it that way, he clearly knew that the crisis was only temporarily alleviated, because as the number one military power in Asia, China's participation in the war would inevitably contain a large number of troops in the navy and army, but the problem was that once China was defeated, the crisis would inevitably return.

Another big problem is that the Allies do not yet have an organization capable of effective communication in the field of intelligence. This is true not only between the United States and China, but also between the United Kingdom and the United States.

(To be continued)