On the way back to Japan from Cartalpas, Samejima was asked, "But why was the ASM-2X loaded on the Akizuki?"
"It's just a coincidence, purely a coincidence."
The people around didn't believe it, but it really was a coincidence.
. . .
Before attacking Duro in the Japanese-Parpaldian War, there was an explanation from the Ministry of Defense to the Cabinet. At that time, the Prime Minister, upon learning about the bombing using BP-3C, inquired if there were means to conduct precision-guided bombing.
Defense Ministry officials mentioned options like LJDAM, but the numbers were limited, so they added, "Alternatively, although it may be costly, the Type 93 anti-ship missile (ASM-2) can perform infrared image guidance, so theoretically, precision bombing is possible... I can only say 'probably' as there are no actual examples."
Upon hearing this, the Prime Minister sighed.
"...After this battle is over, we need to fundamentally reconsider the Self-Defense Forces' weaponry."
Having heard the Prime Minister's words, Defense Ministry officials believed there was a need to increase precision bombing capabilities and instructed the ATLA to consider the possibility of precision bombing using ASM-2.
The ATLA, interpreting it as an official government directive, began the study. When it was confirmed that the schedule would span fiscal years, they submitted a request for the necessary budget. It was then that a misunderstanding became apparent—the budget request did not get approval. While the Prime Minister felt the necessity, he had not explicitly given the directive. When the Ministry of Finance inquired, the Prime Minister's office responded that no such research had been instructed or approved.
In the end, it was concluded that Defense Ministry officials had acted on their own assumptions. However, the ATLA was not satisfied. There was a mountain of equipment, ammunition, and parts that needed to be domestically produced due to the cessation of imports from abroad. Despite the already daunting workload, they tackled this theme as a top priority because it was said to be the Prime Minister's directive. But just as they climbed to the second, third, or even fourth floor, the ladder was pulled out from under them. This research was halted, and the results were sealed—until Samejima took notice and dug it up.
. . .
On the other hand, the Ministry of Defense initiated independent research on the Grade Atlastar. Particularly, it drew significant attention within the Defense Ministry due to its striking resemblance to the old Japanese Navy's Yamato-class battleships. Among various aspects, what was particularly intensively researched was the weaponry to defeat the Grade Atlastar. Various opinions were put forward, but the practical options boiled down to missiles and torpedoes.
However, torpedoes equipped on JMSDF surface vessels were only short-range torpedoes designed for anti-submarine warfare. The platforms capable of launching long-range torpedoes for anti-surface warfare were limited to submarines. While it was technically possible to modify surface vessels to launch long-range torpedoes, the execution posed a rotation problem. Escort vessels undergo maintenance and modification every four years for a period of six months. In other words, if one intended to modify all surface vessels, it would take four years. There was no guarantee that the JMSDF would not face the Grade Atlastar over the next four years, and even if they did, there was no assurance that the surface vessels at that time would be already modified.
Submarines have slow underwater navigation speeds, and the conventional tactic is to use ambush attacks. Even optimistically estimating the opportunities for ambushing the Grade Atlastar with submarines, there were not many by any means.
Thus, the only option left was missiles.
Nevertheless, discussions persisted, especially regarding the warhead of the missiles. If the Grade Atlastar was comparable to the Yamato-class, the vital parts would be protected by at least 410 millimeters of armor. How to penetrate this?
Within the JMSDF, the majority opinion leaned towards HEAT warheads, but there were opposing forces. This opposition came from the JGSDF. Currently, the JGSDF possesses the most abundant knowledge in armored defense. According to them, HEAT warheads could be easily defended against by composite armor. They argued that warships are essentially equipped with natural composite armor.
HEAT warheads use explosive charges. Despite the common misconception that the name implies melting armor through high-temperature explosions, they actually function through the Neumann effect (the phenomenon where even the hardest metals turn liquid-like when exposed to ultra-high-speed gas). With HEAT warheads, it is indeed possible to penetrate 410 millimeters of armor. However, what follows is not as effective. In the spacious environment of a ship compartment, the metal jet (liquefied metal) that drives penetration would disperse. The interior of battleships is compartmentalized finely to prevent flooding, and if only the outermost compartment is flooded, it wouldn't sink the battleship.
This led to a heated debate. According to the Ground and Air Self-Defense Forces, there was no need to forcibly sink the battleship; rendering it powerless would be sufficient. In that case, using existing anti-ship weapons in large quantities to turn the superstructure into scrap would be enough. There was no need to allocate the valuable development resources of the ATLA for battleships. Actually, this argument is not wrong.
However, the JMSDF is not backing down. There was a limitation on the number of SSMs that could be loaded on escort vessels. Unlike SAMs, SSMs were entirely domestically produced. While this was commendable in itself, due to a singular design philosophy, all SSMs shared a common flaw. All SSMs were launched using launch tubes. Once fired, reloading SSMs into the launch tubes was difficult. The reloading process needed to be carried out carefully and was usually assumed to be performed during port visits. Performing it on the turbulent open sea was dangerous, and during combat, it was practically impossible. Due to prioritizing performance, usability had been overlooked. However, calling this a flaw was harsh. When designing SSMs, battleships were not considered as potential adversaries. The scenario of rapid, repeated SSM firing during a naval battle was not anticipated.
Nevertheless, the Ground and Air Self-Defense Forces had no reason to take that into consideration. A ruthless battle unfolded over the limited development resources. Often, it devolved into mere squabbles rather than a rational discussion about how to sink the Grade Atlastar. Some ATLA technical officers actively participated, but many spent a disheartening time feeling frustrated, thinking, "Here we go again."
Samejima, who had been dispatched to the ATLA to address the SAM issue, found this kind of bickering unpleasant. Although he was a JMSDF officer, he leaned heavily towards being a technical officer. After being dispatched, he was surprised by the bleakness of the ATLA's workplace. While the SDF was considerably demanding (especially during crises), the current ATLA either equaled or perhaps exceeded that level. If they lost valuable personnel to overwork, what was the plan? Defense technical officers are highly specialized professionals, and training them takes time and money. The defense industry is a unique field, and unlike civilian product engineers, it's not the kind of occupation that can be scouted externally.
. . .
On that day, Samejima attended a review meeting. On this particular day, the JMSDF had brought up armor-piercing shells. The plan was to turn the warhead of the XASM-3 (at that time, not yet officially adopted, hence prefixed with an "X")—a missile reaching a final velocity of Mach 3—into an armor-piercing shell.
The JGSDF immediately objected to this plan. Tank crew compartments are cramped, and if penetrated, a single armor-piercing shell would undoubtedly result in the death of the crew. However, the situation was different for colossal battleships. Even if it could penetrate, it would be better than a HEAT warhead, but how many shots would be needed to sink a battleship? Moreover, was penetration even possible? It is a major mistake to assume that they can penetrate things just because it is fast.
The JASDF sided with the JGSDF. To enhance the power of armor-piercing shells, it was necessary to increase the warhead's mass. While depleted uranium or tungsten might be used for that purpose, the consequence would be an increase in the missile's mass, reducing the number that could be carried by the F-2s and shortening the range. Thus, the debate intensified and gradually shifted towards a mudslinging contest... or so it should have.
"Um, may I make a statement?"
A slightly hesitant voice echoed. It was Samejima. Those who had been engaged in the discussion turned their inquisitive gazes toward him. One of the JASDF generals among the Joint Chiefs of Staff thought, "Does even the Equipment Agency have a wildcard like Mickey?"
Ignoring the impolite stares, Samejima continued. "I am Captain Samejima, currently seconded from the Maritime Self-Defense Force to the ATLA. Can we avoid falling into the trap of debating for the sake of debating?"
Though those engaged in the discussion felt discomfort, unfortunately, they couldn't deny it.
"We should go back to the basics here. I would like to take a moment to revisit naval history."
Ignoring the judgmental glances, Samejima connected the projector cable to his laptop. Some were about to warn him, but upon seeing the text projected, they swallowed their words.
. . .
"What was the fatal blow to the battleship Yamato?"
. . .
Samejima proceeded to the next screen.
. . .
"A few 1.000-pound semi-armor-piercing bombs dropped from the SB2C Helldiver dive bombers penetrated the armor of the secondary gun turret which caused an explosion. This led to a fire in the ammunition storage, which persisted until the sinking of the battleship Yamato... Ultimately, this single strike became the downfall of the world's largest battleship."
. . .
When the SDF officers saw this, they were not happy.
"So, what's the big deal? We already know that kind of hypothesis without it being said," a staff officer from the JMSDF grumbled. Of course, not all JMSDF personnel were naval history enthusiasts, but enthusiasts were found everywhere.
"The Grade Atlastar is clearly constructed with the same design philosophy as the Yamato-class. Doesn't that mean it has the same weaknesses?"
"So, what's your suggestion then? Should we bomb the Grade Atlastar with a formation of F-2s loaded with Mark 82s?" the JASDF officer who compared Samejima to Mitsugi (or 'Mickey') asked in a mocking tone.
"Of course not. Unguided bombs are too inefficient. We should use precision-guided munitions."
Is this guy serious? The current SDF doesn't have such conveniently effective weapons. That was what the SDF personnel thought before being surprised by Samejima's next words.
"I found out about this after being seconded to the ATLA, but they were researching precision-guided bombing using the infrared IR image guidance of the ASM-2. Currently, it's frozen due to budget issues, though."
Until then, the technicians who had been feeling disheartened all simultaneously turned into serious expressions.
"We have CAD data for the Grade Atlastar reconstructed from satellite images. If there are any incomplete parts, you can supplement them with data from the Yamato-class. In other words, the necessary data is already available."
Samejima pressed the keys on his laptop, and the projector displayed a CG model of the Grade Atlastar.
"The resources needed for development are a few technicians who were working on precision bombing research, the software development environment for the number of personnel, and for testing, a minimum of four live ASM-2 rounds, preferably eight. The necessary man-hours would be more accurately estimated by the technicians involved in the research than by me."
"Is that acceptable?"
One technician raised their hand.
"I believe it should take three to four months for the man-hours required to complete the prototype."
The assembly buzzed with excitement.
"In reality, I think it'll take a bit more time. We'd also like to conduct harassment attacks to interfere with the damage control system, so..."
After Samejima made that statement, the atmosphere in the assembly changed dramatically. The protagonists were the somewhat reluctant technicians from the JMSDF who occasionally responded to questions. During this deliberation meeting, the development plan for ASM-2 Kai was effectively decided. What the JMSDF managed to achieve was to allow the continuation of research on a new warhead missile in case ASM-2 Kai failed.
. . .
This review meeting had a significant impact on Samejima's reputation. The evaluation of the technicians shifted from seeing him as an "unknown figure sent by the JMSDF" to "the only guy in the JMSDF who knows what he was talking about." On the other hand, he was scorned by the JMSDF as a "traitor" or "someone who is already an ATLA member."
Samejima himself dismissed it, saying, "This is a kind of front-line syndrome." Objectively, since the research on the new warhead missile was continuing, the JMSDF didn't incur any losses. Instead, the appearance of ASM-2 Kai, as insurance in case the uncertain completion of the new warhead missile failed, should have been a reason for satisfaction.
However, Samejima is hated. Being resented is akin to soldiers fighting on the front lines hating allies who seem to be relaxing in the rear (even if it's just a perceived notion). It's subtle whether this analogy holds, but the fact remains that Samejima is resented. He had mentally prepared himself to be seconded to the ATLA until retirement. He understood that he had deviated from the elite course, having once struggled with the decision of becoming an SDF officer or an ATLA technician when he joined the agency (back when it was still the Technical Research and Development Institute). He didn't think of it as something significant.
He never expected that gaining the trust of the technicians would lead to his promotion to a flag officer.
. . .
ASM-2X achieved success in the battle of Cartalpas. However, it never became officially adopted as ASM-2 Kai. The Gra Valkas Empire's navy is not stupid; they learned from the lessons of Cartalpas.
Gra Valkan battleships underwent docking and retrofitting one after another. They removed the secondary gun turrets and the critical defensive compartment (vital part) was installed there. While the bridge wasn't removed, its role became limited to tasks such as reconnaissance and impact observation. Instead, a command post was constructed in the place of the secondary gun turret's ammunition storage, where the captain could be stationed to receive reports from various departments and issue orders.
ASM-2X made such a brilliant debut that Gra Valkas swiftly took countermeasures. ASM-2X never became officially adopted, becoming obsolete before that decision was made.