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HoI4 Dev Diary - The Imperial Japanese Navy (AAR)

Hello, and welcome back to another Dev Diary from the frozen wasteland that is Sweden in January. Today, we will have another short AAR of a naval warfare scenario, similar to the one we did earlier about raiding and submarine warfare.


This was played as an MP game between me and Niall (@Ceebie), with me defending the Empire of Japan’s honor against Niall’s filthy American imperialists.


Starting as Japan, I immediately face a number of issues that should sound very familiar: I have very limited resources, particularly in terms of oil. This is now a much bigger issue as I can still happily build ships and airplanes and tanks, but I won’t be able to run them for free. However, if I want to upgrade my ships (and knowing Niall, I absolutely do), I will need naval experience, and China is unlikely to provide me with a lot of it. So I need to run training missions for my fleet, which gobbles up fuel at a rapid pace (I could only take out my main fleet units for a few brief weeks before the fuel situation became critical).


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At the same time, while I could trade for more oil, it will cost civilian factories which I desperately need to build up my own industry or to trade for steel to continue my military buildup. I decided to keep the trading for oil to a minimum in order to more quickly build up my industry and increase the size of my fleet.


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My first target is, of course, China, and we start the war with them in the middle of 1937. It quickly becomes apparent that I underestimate the Chinese. Fighting rages hard along the border for several weeks, and a number of naval landings that attempt to force the AI to draw troops away from the main front are quickly contained by local garrisons, but at least not pushed back into the sea. Part of the problem is that the fleets tasked with invasion support contain some of my battleships, which eat up absurd amounts of fuel, and my attempts to turn the tide through prolific use of air support eat into my fuel supplies even more.


By early 1938, we are slowly grinding forward and have managed to inflict serious casualties on the Chinese, but my fuel stockpile has shrunken to just 30 days of current use. I curtail air support to only support my main thrust and send the naval forces providing shore bombardment back to port. Progress slows, but eventually we link up with the landing forces, at least saving me from an embarrassing early defeat. The massive amounts of Land XP also allow me to run through the doctrine tree quite a bit faster than Niall could ever hope to. Sadly the war in the Pacific will not be fought on land.


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It would take until early 1941 for the Chinese to fall, even though the writing is on the wall by the middle of 1940. I blame the poor infrastructure and awful terrain in China - my leadership is, after all, beyond any reasonable doubt.


In the meantime, Niall has been quietly modernizing his fleet and has started his rearmament. While a good amount of his effort is spent on helping out the British in Europe, I have no doubt that he has something in store for me. While I was deeply engaged in managing the war in China, I received some out-of-game intelligence (Niall bragging in the kitchen that his destroyer swarms would annihilate me) that makes me realize that my fleet lacks some key capabilities. The starting Japanese light cruisers are fairly mediocre, most have been built during the 20ies and are not up to the task of winning a firefight against the likes of a Brooklyn Class cruiser with no less than 3 light cruiser battery modules. What I do have is a lot of torpedoes, and I invest a little into researching upgraded torpedoes and better launchers. The Japanese Long Lance national spirit gives me another perk, as it negates the enemy screening to an extend, which means that my torpedoes can hit his capitals even through 100% screening.


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So while I was slowly grinding my way across China, I also decided on my buildup strategy:


  • No new battleships, since they eat up a lot of fuel and I have enough to cover my carriers. However, I did later decide to build at least one Yamato-class as an insurance against Niall developing modern battleships.

  • A force of 4 light carriers. Japan starts with two (Ryujo and returning fan favourite Hosho), with two Zuhio class building. While these only carry 40 planes each, they will be used to provide cover for operations in and around the Dutch East Indies.

  • A force of 4 fleet carriers, with another force of 4 joining later. Akagi and Kaga will be joined by 2 more Soryu class carriers and form the main strike force in the Central Pacific.

  • A heavy emphasis on air defense and torpedoes. After researching dual purpose main armaments, I design a new destroyer class with improved AA and better torpedo armament. These are joined by a quartet of light torpedo cruisers from the Japanese focus.

  • Lots and lots of Naval Bombers to damage the enemy during the approach and pick off stragglers. Once the battle is fought, his damaged ships would likely try and find a close naval base for repairs, so having naval bombers ready to attack them in port would let me finish them off.

  • Once I identified the fleet’s weakness in defense against destroyers, I also designed a version of the Mogami Class heavy cruisers dedicated to light gun support. I built another 4 of these.

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The fleet’s main objective, however, is to provide support for landings to seize resource rich areas in the Dutch East Indies. To protect the sea lanes to and from these islands, I will need to secure the Philippines, and that is where things get a little dicey.


While I have little doubt that my forces can take over Sumatra, Java and Borneo, Malaya might be a tough nut to crack, and I know that Niall has already started to fortify the Philippines. I have researched amphibious armor well in advance and with China now pacified, I start to turn up production in an attempt to give my marines a bit more punch and hopefully allow me to seize a foothold even against heavy opposition.

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Thinking ahead, I also research improved naval bombers and the next generation of carrier planes. Once my main objectives are secured, I will use swarms of naval bombers to hold them down while I move my fleets to stage two and take on Australia.


To give myself some more time to buildup, I delay my attack on the US until early 1942. This allows me to form a second strike force of two fleet carriers (Shokaku and Zuikaku, both repeat Soryus as I was unable to scrape together enough XP to design an upgraded carrier).


The first battles are very encouraging. Whenever my patrols find one of his scouting units, my strike fleets sortie and make short work of them, Niall’s vaunted Destroyer swarms being no match for my upgraded cruisers and destroyers. I am somewhat confident that I can attrit his screening forces faster than he can replace them, which would eventually force his fleet to remain in port or eat absurd numbers of torpedoes.

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Things quickly turn a little chaotic as my strike fleets and patrols intercept a number of troop convoys. While I first thought that these were going to the Philippines, they instead turn out to be trying to seize islands in the Central Pacific. Things don’t go well for him, as he has decided to keep his battleships and carriers on strike duty instead of covering his invasion convoys. Several divisions are effectively destroyed at sea, and the remains fail to gain any footholds.


At the same time, my invasions in the DEI, supported by the old battleships Ise and Hyuga, have run into stiff opposition while attempting to land in Borneo. I shift some tactical bombers into the theater to help break the stalemate, and we are starting to make progress. The two-pronged assault succeeds in establishing a foothold, but it is a reminder that Niall has not been idle and is ready to fight for every inch of ground in this vital area.

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While my marines still struggle to make landfall in the Philippines, a bigger drama unfolds in the Bismarck Sea. Niall has finally unleashed his main strike force, after one of his patrols found my carrier fleet.


The Battle of the Bismarck Sea does not go particularly well for the Imperial Navy. With several battleships detached for minor repairs, the US Navy breaks through my screening units and manages to do an end run on my carriers, sinking all four for no capital ship loses on their side. The survivors straggle home, many ships badly damaged during the ferocious engagement as my battle line attempted to screen against the full might of the US battlefleet.

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However, Niall’s victory has come at a steep cost. Most of his battlefleet is badly damaged, and he has nothing to follow his success up with. More than that, I still have 6 carriers in reserve (2 fleet, 4 light), and several hundred naval bombers scouring the Bismarck Sea means that he has to risk his battleships again to sail them to safer harbours for repairs. Several of them take further damage as they retreat, many of them out of the battle for almost a year.

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While Niall has blunted my offensive power quite severely, he has nothing to interfere with in my operations in the DEI, which were the main objective. Trying to use the Philippines as an unsinkable aircraft carrier has become next to impossible as trying to supply it with fuel would cost him too many convoys and tank his war support. The Japanese conquest of the southern resource area won’t quite be the lightning strike it was in history, but it is as inevitable as the rising of the sun.

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With hindsight, my performance in the naval war thus far comes down to:

  • Lack of radar allowing Niall to get the drop on me in a critical moment

  • Lack of training due to fuel concerns

  • Insufficient coverage of the seazones with naval bombers failing to disrupt the enemy on the approach

  • Not enough screening vessels to protect my carriers against his battle fleet. Although Yamato sunk several ships and survived to fight another day, spending the same amount of 3 heavy cruisers would likely have yielded better results

  • Good performance of my light forces when engaged on equal terms

That is all for today. Tune in at 1600 CET for another stream with an indepth look at fuel.
 
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Edit: this is response to @Vanadium23's post, a few posts above mine.

Very undecided on Pearl Harbour. The senate idea I actually like, but I dislike the idea of giving the Japanese player "free kills" in the form of a decision.

Also consider this isn't a railroaded game, and Pearl Harbour takes place nearly six years after game start. Trying to make specific historical battles happen this late in the game is always going to be tricky. Instead, you're going to have memorable battles and events that didn't take place historically, but which shape your particular campaign.

Now, if either the devs or modders made a Day of infamy bookmark where the US started with crippled ships at Pearl and a Japanese task force close by, that would be a different story, of course.
How can this be called a historical game without Pearl Harbor?!?! There are plenty of ways to implement it way especially with the new naval system and I feel as though if HOI4 has no Pearl Harbor then Paradox must’ve just given up.
 
Nothing more disappointing than reading and amazing in-depth dev diary to then seen all the comments are childish "release date when?" comments and the order i which they placed.
+1
 
IRL?
"The Japs just decided we we lost nine capital ships. No, there was no battle, they just decided the ships be sunk, and so they just spontaneously combusted".

Nope, I don't consider that good gameplay. Sounds more like how DH (I think) would always auto-resolve the winter war with the historical outcome, regardless of how well the player did.
Just make the focus or decision incentivize both the Japanese and American players to do it with possible pros and cons for both nations to do it but enough to want to go through with it.

EDIT: of course the Japanese player would have to move their fleet into position and so would the United States of America but the outcome for players with historical focus on would be pretty historical and allow for the USA to have a good chance at a comeback but without historical focus on there is now a chance that it will cause damage that the USA won’t recover from quickly enough.
 
How can this be called a historical game without Pearl Harbor?!?!
Isn't that like asking how it can can be a historical game without a carrier battle at Midway, or the Germans being encircled and losing 70 000 men at Stalingrad, or the tide in Africa turning at El Alamein, or the Germans nearly losing the battle of Narvik? None of these are guaranteed to happen either.

HoI4 isn't strictly speaking a historical game. It's got historical jumping-off points, and then lets you do whatever you want from there.

Maybe Pearl is bombed in your campaign, maybe not. Maybe the German army manages to take Moscow. Perhaps there is a surprise bombing of some RAF fleet in port in the Pacific. Maybe the British atmy invades Norway first.

Once you start the war, all bets aare off.
 
Isn't that like asking how it can can be a historical game without a carrier battle at Midway, or the Germans being encircled and losing 70 000 men at Stalingrad, or the tide in Africa turning at El Alamein, or the Germans nearly losing the battle of Narvik? None of these are guaranteed to happen either.

HoI4 isn't strictly speaking a historical game. It's got historical jumping-off points, and then lets you do whatever you want from there.

Maybe Pearl is bombed in your campaign, maybe not. Maybe the German army manages to take Moscow. Perhaps there is a surprise bombing of some RAF fleet in port in the Pacific. Maybe the British atmy invades Norway first.

Once you start the war, all bets aare off.
Well then tell me how in the freaking heck does the USA enter the war legitimately huh?!?! The ONLY reason the USA was brought into WWII WAS PEARL HARBOR and I KNOW that you can’t recreate things like Midway in HOI4 but AT LEAST keep the legitimate way for the USA to join WWII for historical focus on games.

EDIT: also it would be Royal Navy Fleet not RAF Fleet that would be aircraft and honestly if there is no longer a legitimate way for the United States of America to enter the war (as even in an althistorical game the USA would have no grounds to join the war as most of the American public would still be against it without Pearl Harbor) then I may never play my own country again as without any legitimate way to join the war I would feel like the Government forcing its’ people to go to war.
 
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Well then tell me how in the freaking heck does the USA enter the war legitimately huh?!?! The ONLY reason the USA was brought into WWII WAS PEARL HARBOR and I KNOW that you can’t recreate things like Midway in HOI4 but AT LEAST keep the legitimate way for the USA to join WWII for historical focus on games.

EDIT: also it would be Royal Navy Fleet not RAF Fleet that would be aircraft and honestly if there is no longer a legitimate way for the United States of America to enter the war (as even in an althistorical game the USA would have no grounds to join the war as most of the American public would still be against it without Pearl Harbor) then I may never play my own country again as without any legitimate way to join the war I would feel like the Government forcing its’ people to go to war.

In game it happens by the japanese Empire declaring war on the US, as IRL.

The declaration was delayed past the attack, but was planned to be given 30 minutes prior.

So, game mechanics wise, you would have Japan Dow the US. War begins.

I mean, without Pearl harbour but with the japanese declaration of war the US would have remained Neutral?

Impossibru!!
 
@Tristan Edge Are you guys going to make it where Pride of the Fleet ships give +% of war support based on the number of kills that ship has? It would incentivize players to not just keep their Pride of the Fleet in their port for the whole war.
 
In game it happens by the japanese Empire declaring war on the US, as IRL.

The declaration was delayed past the attack, but was planned to be given 30 minutes prior.

So, game mechanics wise, you would have Japan Dow the US. War begins.

I mean, without Pearl harbour but with the japanese declaration of war the US would have remained Neutral?

Impossibru!!
If Pearl Harbor never happened then the Japanese would’ve just bypassed the Philippines or stole the Philippines without declaring war and the America as the Japanese pretty well knew that the American people wouldn’t support a war unless 1. A certain number of casualties to an attack, 2. Something that effects the American people profoundly enough or 3. A direct attack on the USA mainland, Alaska or Hawaii.
 
If Pearl Harbor never happened then the Japanese would’ve just bypassed the Philippines or stole the Philippines without declaring war and the America as the Japanese pretty well knew that the American people wouldn’t support a war .

So, pretty stupid of them to do Pearl harbour then.

Nothing to gain there.

The japanese government knew of course fully well that one way or another, the US would sooner or later enter the war. They figured a preemptive strike would allow them to force a truce.

So, no. Bypassing phillipines is a very ahistorical option and would maybe been reality If Landon or some other Isolationist had been elected.

But FDR was doing anything to fight the fascist powers before Pearl harbour and would have provoked a clash with japanese forces If Pearl harbour didn't happen.
 
This could be the perfect jump in for the next DLC, dealing with espionage and reconnaisance methods:cool:
completely agree. the japanese knew well that the "big 7" are in pearl harbour, so it would be cool to see something like a system where you would know roughly how many ships are based in a port depending on your intelligence effectiveness. something like 6-8 bbs, 4-5 cas 4-5 cls and 50-70 dds are based there. ofc during war it would be harder to get actual information so there should be cases when you don t realize big ships were "rebased" or launched, just as the usn didn t realize they sunk the shinano, the biggest carrier oof the war (3rd yamato class bb conversion) only after the war since they just didnt know it existed.. also naval aerial recon was insanely important, and i believe this is the field where an air rework would start to shine, so you could build floatplanes which would operate from ports, not airfields ;)
 
If Pearl Harbor never happened then the Japanese would’ve just bypassed the Philippines or stole the Philippines without declaring war and the America as the Japanese pretty well knew that the American people wouldn’t support a war unless 1. A certain number of casualties to an attack, 2. Something that effects the American people profoundly enough or 3. A direct attack on the USA mainland, Alaska or Hawaii.

Congress was already shifting towards pro-war without a Japanese attack on the US or the West and FDR who already had one foot in the war would likely have been able to enter the US officially onto the Allied side in 1942 regardless of whether or not the Japanese went to war with the West.
 
Congress was already shifting towards pro-war without a Japanese attack on the US or the West and FDR who already had one foot in the war would likely have been able to enter the US officially onto the Allied side in 1942 regardless of whether or not the Japanese went to war with the West.
agreed, although the us war support would have been closer to the early-war french or english war support (which was quuuuite meh)
 
If Pearl Harbor never happened then the Japanese would’ve just bypassed the Philippines or stole the Philippines without declaring war and the America

How do you propose that Japan could have "Stolen" the phillipines guarded by US Army, Navy and Air forces present without attacking those forces or declaring war?
 
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Well then tell me how in the freaking heck does the USA enter the war legitimately huh?!?!
You sound upset.

  1. The US declares war when ready. They were were at a de facto state of war with the axis anyhow. They had even started hunting German subs in the Atlantic.
  2. The Japanese does something else to pull the US into the war.
  3. Germany does something to pull the US into the war.
  4. Some Some other power pulls the US into the war. Remember, HoI 4 is a sandbox. Maybe the Soviets invade Alaska, who knows.
Either way, if the US officially joins the Allies earlier or later than December 1941, so what. Just another way you can change history.
 
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Its clear to me youve never played hoi3 or at least you are very bad at it and never got far (99.9% of hoi4 fans) because if you did you would realize that fuel, stockpiling, ship customization and modules were ALL in hoi3,
now being ripped out and sold to hs for 19.99.

Anyone that played HoI3 would know that it had less ship design options than HoI4 vanilla has. In HoI4 you can design 20 different variant upgrades for each 4 years of ship tech, while the same options for HoI3 was 8-12 different upgrades ( depending on type of ship ). It seems to me that you are the one that never played HoI3.

Yep, the game is almost starting to look like hoi3 and it only took them 3 years.

Hoi4 doesn't look anything like HoI3:

full-10095-23742-research.jpg
 
Yeah, HoI 3 just let you choose to downgrade a ship designe to obsolete guns, armour, etc. if you wanted to.
 
You sound upset.

  1. The US declares war when ready. They were were at a de facto state of war with the axis anyhow. They had even started hunting German subs in the Atlantic.
  2. The Japanese does something else to pull the US into the war.
  3. Germany does something to pull the US into the war.
  4. Some Some other power pulls the US into the war. Remember, HoI 4 is a sandbox. Maybe the Soviets invade Alaska, who knows.
Either way, if the US officially joins the Allies earlier or later than December 1941, so what. Just another way you can change history.
I don’t want to change history AT ALL.
I don’t want to play a United States of America that forces it’s people to go to war without their support and I DO NOT want to play a game that completely removes one of the most important events in history just because it isn’t easy to implement even though they already had something there that they could’ve worked with.