Most likely we would see a London Naval Treaty or a Paris Naval Treaty concluded in 1923 after the Great Kanton Earthquake with Britain USA France and Italy having a slightly superior ratio compared to Japan.
This ^ I think that sometime in 24-25 they get back together in London and agree to a new treaty.
The differences from OTL would be, that ship limit is probably more like 43-45,000t and 16" guns.
This is assuming,
- no 18" ships have been built, I think this is likely as no US plans and IJN/RN (no13/N3) would not have been started/competed by this point.
- No larger ships apart from the 4 G3s have been built ie limit is SD/Lex/Tosa/Kil/Amagi with G3s exempted in balance for smaller/older RN ships
- Cruiser stay at same size limit
Ratio wise,
- US/GB where happy with OTL WNT ratio
- Japan will be in a weaker position but then she might also have weaker ships v OTL WNT (not the post LNT cuts that we remember from WWII !)
- Fr/It are irrelevant and have build nothing since
Ship wise (by class or its to long!)
USN 6x SD 6xLex 4x Col, 2xT, 3xNM, 2x P, 2xNe , 2x NY......small stuff with 12" (assuming several of the Lex are not being redone as CVs?)
RN 4x G3, Hood, R&R, 5R, 5QE, Tiger, 4ID, many 13.5" and then 12" ....... (also pretending to start work on N3s but not actually wanting to spend the money)
IJN 4x Amagi 2x Tosa, 2x N&M, 2x I, 2x F, 4x Kongo,.......obsolite other small stuff (can they afford to finish all of that and even think about also Kii maybe building slowly but Owari has been bent by the quake)
MN old
RM old
So to balance them on WNT ratio trying to move toward 15,15,9,5,5 (US/GB/J/F/I) but actually allowed more at the start 18, 22, 10, 7, 6 (LNT was 15,15,9).
US would want all standards and potentially the two NY as training ships this cuts all 12" ships?
Say they get 6x SD 3xLex 4x Col, 2xT, 3xNM, 2x P, 2xNe = 22 ships + 3 Lex as CVs and 2 NY as TS
RN would want to match USN,
4x G3, Hood, R&R, 5R, 5QE, Tiger, 4ID = 22 with a couple of other 13.5" as TS
IJN would need 13 ish ships to match,
1x Kii, 4x Amagi 2x Tosa, 2x N&M, 2x I, 2x F, 4x Kongo = 17 they would need to cut 4 ships, I think converting two probably still uncompleted Amagis to CV and cutting two 14" ships (not sure if they cut F or Ks ?)
1x Kii, 2x Amagi 2x Tosa, 2x N&M, 2x I, 2x F, 2x Kongo
F/I can keep everything until they build new (or don't due to money) like OTL treaty.......
Long term effects.....?
- RN is stronger compared to European navy's and faster (and industry is stronger) this makes WWII in europe 39-41 easier for GB at least at Sea.
- Japan will have had more evidence that it cant fight US/GB in a long war as it can easily be out built, what effect does this have on Pacific war. (also that the anger of US code breaking is out earlier and this has less effect as Japan has to accept it due to quake/economy?)
- A 10 year holiday from 25 (ITTL L/WNT) will last until 1 JAN 1936 by that point this probably brings forward some building as its likley ITTL 1LNT is more like 2LNT ie no holiday/cuts but more just keep limits and build some new ships?