Shipbucket

Wonder how this happened?



That is a first draft work in progress.

Well... see below, the 1932 refit.

Comments and criticisms, always welcome.

Hi Tobius. One question, in your AU SMS Lutzow survived the war to be given as war reparations? Cheers.

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The Germans scuttled her post Jutland in the RTL after her speed fell off and she could not keep up with Hipper's other cruisers. He had to take his flag off after the DC parties were unable to halt the flooding forward. In my opinion, it was a typical German performance, rather heroic but not too well organized. Harder made some serious mistakes that allowed the flooding to snuff out his engines. Derfflinger was just as hard hit but managed to stay afloat because her engine rooms were kept in service to power the pumps. In addition, the British kept hammering Lutzow long after she was kaput.

In this AU, the flooding is halted at frame 20 and the ship survives. I think Mitchell will want her instead of the Ostfreisland, but as far as I'm concerned the SMS Lutzow (USS Lake Champlain) is an American HMS Argus. The cruiser will be the gadget like Langley was to try out new stuff.

IMPLICATIONS:

In the RTL:

General characteristics
Class and type: Proteus-class collier converted into Langley-class aircraft carrier
Displacement:
19,360 long tons (19,670 t) (as Jupiter)
12,700 long tons (12,900 t) (standard, as Langley)
13,900 long tons (14,100 t) (full load, as Langley)
Length:542 ft (165.2 m)
Beam:65 ft 5 in (19.9 m)
Draft:27 ft 8 in (8.4 m) (as Jupiter);24 ft (7.3 m) (as Langley)
Installed power: 3 × boilers 7,200 shp (5,400 kW)
Propulsion:
General Electric turbo-electric transmission with 2 × shafts
Speed: 15.5 kn (17.8 mph; 28.7 km/h)
Range: 3,500 nmi (4,000 mi; 6,500 km) at 10 kn (12 mph; 19 km/h)[2]
Complement:163 officers and men (as Jupiter); 468 officers and men (as Langley)
Armament:
4 × 4 in (102 mm)/50 cal guns (as Jupiter)
4 × 5 in (127 mm)/51 cal guns (as Langley)
Aircraft carried:None (as Jupiter); 36 (as Langley)
Aviation facilities: 1 × elevator and 1 × catapult

The Langley was a kluge intended to test out ideas, an experiment ship to thrash out the ins and outs of aircraft reconnaissance and air support from ships. It was never intended to be more than a such an experimental vessel, though if war came she would be used as an aircraft carrier.

=======================================

Class and type: Derfflinger-class battlecruiser converted into a Delaware Bay class aircraft carrier
Displacement:
26,741 t (26,319 long tons; 29,477 short tons) design load as a battlecruiser
24,700 t (24,310 long tons; 27,227 short tons) design load as aircraft carrier )
Length: 210.40 m (690 ft 3 in) overall at wl; 215.0 m (705 ft 3 in) at flight deck
Beam: 29 m (95 ft 2 in) as battlecruiser; 33.4 m (109 ft 6 in) as aircraft carrier (includes torpedo blisters and overhangs)
Draft: 9.20 m (30 ft 2 in) as battlecruiser; 7.9 m (25 ft 11.5 in) as aircraft carrier
Installed power:
18 water-tube boilers
59,567 kW (79,881 shp) (trials)
Propulsion: 4 shaft steam turbines
Speed: 26.4 knots (48.9 km/h; 30.4 mph)
Range: 5,600 nmi (10,400 km; 6,400 mi) at 14 knots (26 km/h; 16 mph)
Complement: 44 officers, 1,068 men in German service as battlecruiser; 108 officers and 1,214 men as US aircraft carrier.
Armament: as battlecruiser;
8 × 30.5 cm SK L/50 guns
14 × 15 cm SK L/45 guns
8 × 8.8 cm SK L/45 anti-aircraft guns
4 × 60 cm (24 in) torpedo tubes
as aircraft carrier;
6 (3 x 2) 15 cm BLNR (SA) BK L/30 guns
14 × 2.0 cm Hotchkiss AA guns
Armor:
Belt: 20 cm (7.9 in)
Conning tower: 20 cm (7.9 in)
Hanger Deck (as strength deck: 3 to 8 cm (1.2 to 3.1 in)
Turrets: 2.55 cm (1 in)
Aircraft carried:
48-50 aircraft; split in 1930 evenly between two squadrons of Boeing F4B fighters and two squadrons of Great Lakes Aircraft BG scout bombers. (Note that the US Navy did not have a working air dropped torpedo until 1932.)
Aviation facilities:
3 × elevators
2 × flight deck electric catapults
1 × hangar deck hydraulic catapult

FLUFF:

The conversion of these three German ships was problematic and difficult. Derfflinger and Lutzow were badly damaged at Jutland and thus serious hull reframing had to be undertaken along with the fitting of "torpedo blisters" to countervail the needed overhang of the flight deck superstructure that replaced the former battlecruiser top-works above the strength deck. As the separated fire rooms induction and exduction piping to the offset stacks could not be trunked together without a crippling effect on the hanger working spaces and travel paths for the hangered aircraft from the starboard strike below deck edge lift to the port feeder deck edge lift catapult; called for in the C & R Bureau's master work up for the flattop, the awkward split funnel arrangement and the compromised island and gun armament arrangements results.

It was hoped to obtain an operational air group of 60-65 aircraft on the hulls, but as it worked out, even with the conversion to oil fired boilers and the straight run offset funnels, the ships were too small to operate more than 40 aircraft comfortably or 50 on an extremely crowded flight deck under wartime conditions. Peacetime air group strengths were authorized at 32 aircraft.

SMS Derfflinger => USS Delaware Bay where the Continental Navy trounced the British in the Revolutionary War.
SMS Lutzow => USS Lake Erie, the USN sort of kiboshed the Royal Navy in the War of 1812.
SMS Hindenburg => USS Saint Simon's Island, The US state of Georgia's naval militia beat the RN again.

One senses a theme?

Looks like the images were resized. Your image also looks very unfinished, is it a work in progress?

_________________
Drawings are credited with J.Scholtens
I ask of you to prove me wrong. Not say I am wrong, but prove it, because then I will have learned something new.
Shipbucket Wiki admin

Concept stage. Shading will be in the final.

I need another image hosting service.

Anyway, this is a continuation of Mister McKinley's Navy to about 40 years later.

THE TRENDS:

In Europe, there is a continental four way arms race; with France, Germany, Austria-Hungary and Russia engaged in a headlong gallop to see who can blow up the continent first. Great Britain, behind her steel wall of a navy, looks on with growing alarm, for Germany's Kaiser Wilhelm II thwarted by the United States in the Pacific, and then forced to slink off from Venezuela when confronted by the American navy, again; has embraced the doctrine of the Risk Fleet as expounded by Admiral Tirpitz, that is to create a German navy strong enough to prevent the British from dominating European waters. Tirpitz argues that this fleet will make Germany a natural regional ally to Britain against Russia and France, such as Japan has been to the British in the Pacific.

This idea leads to a naval arms race similar to the one France and Britain had in the 19th century because Tirpitz obviously knows nothing about how seapower actually works. Tirpitz is right about Britain looking for a regional ally, for Europe, but it is France which fills the role, not Germany; because the British will ally with the #3 power in the region, never the # 2 power. If Tirpitz had studied the Napoleonic Wars, he would have known that fact. Mahan did. He predicts as early as 1904 that the Germans and British will be in a battleship building marathon that will culminate in mutual catastrophe for both nations, somewhere in the North Sea as both fleets misapply his doctrine for decisive battle. That Mahan knows the British see the High Seas Fleet as a blockade breaking force that will attack British trade routes should the British home fleet lose sea supremacy in the North Sea is lost on Tirpitz.

All the Risk Fleet actually does is exhaust German finances, robs her of key technical means and personnel, weakens her land armies by a crucial 15% and results in a Central Powers and Allies stalemate by 1917. Russia collapses from military exhaustion and governmental incompetence, a national characteristic that historically requires strong man psychopaths to overcome. Lenin supplies that remedy, but civil war sort of removes Russia from the order of Allied battle. You can shuffle events and pieces about as you wish, but the balance sheet in this AU as it was in the RTL will result in the same bloody awful end result. Both sides run out of men and moral to carry the issue against rapid fire artillery, barbed wire and machine guns. Not even Britain’s tanks and France’s airplanes are going to solve it in this war because the manpower and the know-how is not there to beat the better led and trained Germans without help.

And the U-boat war at sea, with Britain’s muddled response; despite (in this AU) the Spanish American War’s warning lessons does not help.

The United States is the natural source for that aid to tip the balance. In British and French calculations, it is her manpower that will be the numbers difference. So they appeal to her.

Wilson is willing, the fool, but he has a Republican opposition led by Roosevelt and Lodge who see no advantage for the United States in the issue. They urge a sit-out until America can call the shots. Let the Europeans kill each other and bankrupt themselves. The United States can profit from the war and from the peace of exhaustion as she takes over British, French and German financial interests in the meantime and when she sells the survivors her services after the war fizzles out. Business is business.

In the nonce, to prepare for the upcoming role of leading world power, the Republicans in Congress join with Jingo Democrats and push through a series of Navy bills starting in 1912; that has the avowed goal, not publicly admitted, of supplanting the Royal Navy as the leading naval power.

By 1920 the USN will be in a position to do to Britain, what Germany cannot do, which is strangle British trade. That is the heart and soul of the Infamous Sims 12-6 Plan. Sims has his heart set on it. He is an Anglophile, but he smells British blood in the water and he is an American first.

The series of clashes in the North Sea, between the Grand Fleet and the High Seas Fleet, reveals some unusual technical lessons to him.
----a. The British designed their navy for “global conditions”. They went for good seakeeping, large guns, and long range gunnery which involved complex and rather fragile centralized fire control systems. This was Jack Fisher’s doing, he being Great Britain’s great naval innovator and experimenter who believes in gadgets, new ideas, and machines over men and tradition. The results are mixed. Some of the ideas; like his coastal bombardment ships and to use battlecruisers as scouts are insane; but some of the ideas, such as gunnery practice over fleet parades should have produced sterling results. They don’t for sundry reasons having to do with Fisher’s inability to cull the British naval officer corps of men such as Beatty, overcome the not invented here mentality of the RN technical services, and the astounding lack of skill as the war continues at sea to develop either a reliable decentralized command system or such simple things as viable useful damage control doctrine. Sad to say, RTL, this continues in the RN to the bloody present.
----b. The Germans designed their navy for the North Sea and Baltic. They went close combat, large numbers of rapid fire guns in all calibers, thick armor and sacrificed seakeeping and habitability to maximize those attributes in ships. Their fire control systems were man-centered, not machine, and they practiced damage control and fleet battle maneuvers drills like a naval religion. Most importantly, as they did in the Herr, they used a naval version of Moltke’s battle-management style. Subordinates were told what needed to happen, but not how to do it. Scheer may not have been a tactical adroit like Jellicoe, but the entire German naval officer corps, top to bottom was not riddled with men like Admiral Beatty and Admiral Evan Thomas. Scheer could escape his mistakes, because his subordinates were excellent ship tacticians and they could improvise. Jellicoe could not close the deal because his subordinates could not think for themselves and were afraid to act decisively without his detailed top-down instructions. They were and are not the incompetents, amateur naval buffs may make them out to be, but they were not trained to operate a modern navy the way it should be handled. They were stuck back at Trafalgar. The Germans with a clean sheet of paper navy, were more industrial age minded. Men mattered more, not less.
===>c. America can profit from British and German experience by not following their mistakes. It shows quite plainly. The British, both in the U-boat war and in the North Sea at the tactical level and to a certain extent, in the technical art, are completely outclassed. And the USN notices it. Battlecruisers, a fad, which the USN first proposed to Congress in 1909, suddenly seem like an expensive idea and mission that can be better handled by the fast armored cruiser with reliable radios; something that both the Spanish American War and the Russo-Japanese War actually teaches if one looks at the details. Huge unwieldy fleets waiting on instructions to deploy in single line of battle take too long and are too slow and cumbersome to react to events. When the admiral cannot see the end of his line and the means to command is the radio, not the signal flag, then decentralized direction of sub-units is the only option left. And in this milieu, eyes in the sky to find the enemy and sort out the entire surface of the battle area becomes rather essential for charted deployments of fleet subunits and radioed orders. The British have the means, but possess no doctrine in the seaplane and wheeled plane carrier. The Germans with the doctrine choose the wrong reconnaissance means in the Zeppelin. The Germans lose three of the four North Sea battles because they can not see the big picture. with too few [unreliable and fragile] aerial scouts. The British have the planes, even could sort of communicate; but Jellico has no trained signals organization or naval admiral's staff system to collate the reports, whip up a quick response, or even have the captains who can be relied upon to show initiative. Sims knows first-hand the character of the Royal Navy command setup and the men so handcuffed by it. He is friends with many of them, but he is not blind to their faults. With the Germans, Sims has to guess more.

==================================

World War I on land is a dilly. The French never get a good machine gun (No Hotchkiss) so they have to lean on British loaners (Vickers) after the St Etienne fails them. On the other hand, the British don’t get the Lewis either. (Same reason. The American inventers stay home.) The Germans use a mix of Schwatzlose originals and Spandau copies of the Vickers and their woes are much like the Allies. Those water cooled machine guns are heavy. The French, British, Italians and Germans all spend the war looking for solutions that sort of replicate RTL results. In the AU, none of them are very successful either. Hiram Maxim reigns supreme. The French and Germans get into a scout/fighter technical race that soon pushes the fixed wing airplane to astonishing levels of performance that a peacetime generation of tinkerers could never achieve. RTL or AU, the result is the same. Instant obsolescenc e equals death. This is something brand new. Nobody has seen a technology race inside a war before. It is not like the horse stirrup or the bayonet, a gradual dissemination of technology. The French invent a method to shoot through a plane’s propeller disc. The Germans are in trouble until they surpass the achievement with a trigger interrupter of their own.

And then there are the British off to the side tinkering away. And it is at sea. For U-boats they develop the depth charge and the hydrophone to attack them. To find U-boats, which swan about still mostly on the surface only diving to escape a surface ship, the British develop the aircraft carrier and the naval bomber, either wheeled or floatplane launched from a ship. And again the USN observes these antics. Whether RTL or AU these are the trends.

The Germans think Zeppelins are the way to go for naval reconnaissance. The USN notices this factor, too.

So, the USN immediately wants to send scout fighters to sea to negate both threats. There will be American aircraft carriers.

IMPLICATIONS:

a. The American navy will operate the American air arm, period. Reconnaissance is life.
b. The Lexingtons (all 6 of them) will never be finished as battlecruisers.

General characteristics
Crew: Two: Pilot, Torpedo Officer, Navigator, Radioman/Gunner
Length: 11.25 m (37 ft 1 in)
Wingspan: 50 ft 0 in (15.24 m)
Height: 4.60 m (15 ft 1 in)
Wing area: (41.8 m²) 450 ft²
Empty weight: 2,994 kg (6,600 lb)
Loaded weight: 13,200 kg (11.220 lb)
Max. takeoff weight: 13,200 (29,101 lb)
Powerplant: two × Pratt & Whitney R-1830-64 Twin Wasp radial engine, 900 hp (672 kW) each
Performance
Maximum speed: 435 k/h (230 knots, 270 mph) at 16,000 ft (4,800 m)
Cruise speed: 206 km/h (111 knots, 128 mph)
Range: 1700 km (918 nmi, 1054 mi) with 1 x 1000 kg (2,202 lb) bomb, 1,152 km (623 nmi, 716 mi) with Mk XI electric torpedo
Service ceiling: 9,400 m (30,840 ft)
Rate of climb: 12.95 m/s (2550 ft/min)
Armament
Guns:
4 forward-firing 1.27 cm (O.5 in) machine guns or 2-4 x 2.0 cm (0.79 in) auto-cannon
Bombs:
1 × Mark XI electric torpedo or
1 × 1,000 kg (2202 lb) bomb or
2 × 250 kg (550 lb) bombs or
12 × 50 kg (110 lb) bombs

AIR AGE FLUFF:

When you look at the goings on in the real time line from 1914-1928, the trends in aircraft development show engineering progress along two tracks. The military planes of the era for all that they adopt metal fuselages and shock mounted undercarriages and benefit from the German WW I research on thick cord wings are still mostly biplanes with wing struts wires and fixed undercarriages. The engines range in performance from 200-450 kW (in US iterations) and are mostly single engine or twin engine machines.

In the civil market, both in Europe, the British and French Empires and the continental states, there are variations on this military theme with the French and the Italians in the RTL being competitive leaders and the British and Americans being close seconds. Mostly this is a result of government mandated and underwritten civil aero engine research and trophy air racing going on (Schneider Cup being the most famous example) but there were the Bendix Trophy the Fairmont and other "private" publicity events giving growth and recognition to nascent the civil aviation industry. The French and the Italians will eventually falter because the impetus to achieve concrete technological results cannot be bureaucratically mandated. Bureaucracy tends to inhibit risk takers. Giant empires with a need for long range mail carriers and who can award airlines with guaranteed government haulage contracts will drive aviation development in the 1930s. Those players are Great Britain and the United States. You will notice RTL, that Russia, Japan, and Italy will license manufacturing rights to British and American radial aero engines? And even at that, the Americans, themselves, after their bureaucratic mandated hyper-engine program fails, will wind up buying privately developed BRITISH liquid cooled engines to power some of their fighters? Capitalism and geography is the key to understanding how these trends happened. You can have a Jack Northrop and an Ed Heinemann in your hip pocket, but if the engines are not there, then the well designed planes simply will not work. That is RTL American aviation in a nutshell about 1930. Britain, that strange Fabian socialist class bound society goes the capitalist route to service their empire. Their aircraft designers with the exception of De Havilland's generic gnomes and that lone genius R.J. Mitchell are not very good at slide-ruling something that will fly right, but they do get those engines. Napiers, Bristols, Rolls Royces, turn to any compass point and any aircraft requirement and the British have an engine to fit the needed plane. And they have it all by 1930. That too is RTL.

Continental Europe you say? The Germans have engines. Of course they do, but wattage class for class and for engine type, despite some ingenious work arounds and aspiration (fuel air injection) solutions, the German aero-engines are heavier, burn more liters gas per kilogram and underperform against their British and American rivals. You get heavy engined fragile framed (to save weight) German aircraft. And in the RTL, those airframes are outrageously poorly designed. Willy Messerschmidt and the Dornier Bunch being glaring examples. Heinkel cannot be everywhere to fix all the mistakes.

==============================================

GEOPOLITICS FLUFF:

There is in the RTL the Nine Powers Treaty for the Pacific that deals with China. And in Europe there is theVersailles Treaty. Strictly from the RTL American point of view although I doubt that it is taught this way anymore, the Versailles Treaty was a scrap of waste paper the American government ignored. American treaties with the Central Powers or their successor states had to be separately negotiated as a series of formal peace treaties after Senator Lodge put the kibosh on President Wilson's attempt to sell the American nation on the League of Nations which was a centerpiece of the European imperialist system encoded in that Versailles Treaty. It was abundantly clear, that the idea of collective defense of the European system status quo could be the only intent of such a treaty provision.

Not many Americans were ready to sign a blank check to preserve the British or French empires. Not after what they had seen when they went "over there".

The Nine Power Treaty on the other hand was an American sponsored treaty in the RTL, a rather forgotten addenda part of the 1922 Washington Naval Conference that was convened to tamp down or prevent a naval arms race between the US, the UK and Japan. If anything, it was part of a diplomatic package even more complex and confusing than the Treaty of Versailles, because it sought to stabilize the strategic positions of the five major naval powers globally, and to establish technical ground rules for international relations in China, by extension the Pacific and do in diplomacy what the naval arms limitation treaty sought to do for battleships, and other ship classes in hardware. Note that CHINA was not really consulted as to how this treaty would operate?

Stripping away all the folderoy and obfuscation, the 9P Treaty was US designed to do three things:
----a. Keep American commercial activities in China unhindered by France, Britain, Japan and especially China.
----b. Pry apart the British/Japanese common interest to oppose American imperialism in the western Pacific; that is as another wedge to convince the British to abandon their Japanese regional ally.
----c. Ram down China's throat just who was the top dog in the Pacific. That went for Japan and Great Britain, too.

It actually, as part of the Washington Naval Conference, worked beautifully for about 20 years with the case of Great Britain. Japan, not so much, though I would argue that it did force the Japanese to be somewhat cautious until 1931. In Britain's case, it permanently achieved the American objective. of displacing the British as the premier international power anywhere. Once the British conceded American parity not only in naval terms but also in diplomacy, adopting a foreign nation's international policy as their own and signed on to the American Open Door Policy to which they had never really committed prior, they were through dictating anything to anyone ever again. You can almost date the death of the British Empire to 6 February 1922, though I doubt the British crown government realized what happened to them.

I don't actually blame them. WWI had a traumatic effect on its participants to the point that most governments were desperate to avoid what were perceived as the mistakes that led to it. So how did it RTL happen that the British agreed to American terms? The British thought the English-speaking Americans could be reasonable and be talked out of a naval arms race. The Americans took advantage of that British mistake and pretended to agree with "British" proposals . France and Italy being regional naval powers were more or less helplessly dragged along, powerless to affect the proceedings. Japan was the other shark at the table and was not too happy with the game the Americans rigged up and THEY SAID SO. You cannot even create an AU in this historic period without understanding what really torqued the Japanese off, and why the US did what it did to Japan as a result of the British game.

PARITY:

It seems ridiculous in hindsight, what the Japanese argued at the Conference both diplomatically and technically in 1921, but here is their position. First; they did not demand exact numerical equivalence. What they requested (yes, they requested.), was a unit force ratio of 7 to 10 as opposed to the force ratio of 3 to 5 which the United States insisted was its bottom concession.

Diplomatically, the Japanese cited their special position as an "Asiatic nation" entitled them to a special status as China's protector against European imperialism. This status, they insisted, gave them unique political and military rights within Chinese territory. Most of the Conference participants knew that 1921 Japan meant against communist Russia, but the Americans also knew the Japanese meant THEM, too. That was where the naval force ratio argument came in. The Japanese expected a visit from the USN in their future and according to the best kriegspiel of the day, all other factors being equal, to mount a successful naval defense, the weaker naval power needed at least 3/4 the strength of the attacker fleet. The Japanese took this to mean literally that they had to have 3/4 the units and 3/4 the tonnage and 3/4 the types. There might be wriggle room if, say for example, the defender were allowed cruiser numerical equality a weaker ratio in destroyers might be traded, but on the battleships, it had to be 7 to 10.

The Americans either misread the Japanese or accepted the same lunatic arguments the Japanese did. They wanted and stuck to a 3 to 5 class by class, unit by unit, and total tonnage by tonnage force ratios. They even went so far as to concede a Japanese request that no new Pacific fortifications outside Hawaii be built to coax the Japanese to agree to it. Grumbling all the way, the Japanese agreed, but privately among themselves said the westerners had caused them to lose face, treating them as "inferiors". The Japanese historically cite the Washington Naval Conference shenanigans as a key cause for why their nascent constitutional monarchy failed by 1932.

The Americans know all about the Japanese government's political difficulties that was tied to their negotiating position, because the Americans broke into Japanese cyphered diplomatic cable and radio traffic. Needless to say, the Americans (This conference is being held in Washington.), broke into British, French and Chinese traffic too. The Italians they just wined and dined and honey trapped. (Why do you think the British insisted on London for the next conference.)

Anyway, the 9P Treaty delays a Pacific War and so does the WNT. So was that force ratio argument significant at all?

Depends on some assumptions. In 1921, it might be argued that battleships matter, and that such simplistic force ratio calculations are a matter of national survival. One of the reasons, Jellico in WWI and King in WWII refused to release destroyers for convoy duty was because there was an enemy battle fleet that those destroyers needed to be concentrated to fight. Whether they were right is not relevant. They thought they needed to protect their battle lines from enemy destroyers and so they calculated accordingly. For officers who are still taught the cube root artillery gun-power method for total fleet combat potential, those force ratios are holy writ. And yet in the RTL, when the matter is tested in war, it turns out that the WNT force ratio argument fails. When the USN finally attacks in the winter of 1942, they are still outnumbered roughly 10 to 9 in force ratio by the IJN in all classes of ships and aircraft and in trained personnel in the Pacific. It can be argued that they do not achieve the Japanese accepted 7 to 10 defensive force ratio numerically until March 1944. It is at that 10 to 9 ratio, that the Japanese start to lose spectacularly in the air and in naval surface battles. That is the RTL Pacific War. If the Germans have the myth of the Russian hordes that beat them in the Eastern front, so the Japanese have the American hordes myth in the Pacific War. That is curious, is it not? 4/5 of America's power was headed into Europe and yet with 1/5 of her might, the Americans prosecuted a remarkably swift 28 month offensive war against an enemy who for most of that campaign had "paper" parity.

Obviously something went missing in Japanese and American calculations, pre-war. What was it?

Air-power. Not planes or even aircraft carriers numerically, because Japan was able to field huge air fleets right to the end of the war. The hint is Midway and the Solomons/New Gunea campaigns.

Pilots, training time and attrition. The Japanese were not prescient. They should have insisted on no new airfields outside the national territories, (Hawaii and MIDWAY would not receive those valuable runways.) limited numbers and types of aircraft and insisted on even stricter aircraft carrier tonnage limits in the Washington Conference negotiations. The Japanese thought aircraft carriers were an equalizer. Against the nation that invented the airplane and was a leading investigator of naval aviation???

But in 1921, who would know? In this AU, I will make some slight small adjustments.

AU start maps.

Treaty of Cologne.



Treaty of Manila.



Maps: (Univ of Indiana), altered by Tobius