Impressive explanation, thank you for taking the time.
History is kind of a hobby for me, and as a biologist/ecologist there are a lot of parallels I can draw with ecology and evolution. The 1922 Washington Naval Treaty had a lot of interesting wrinkles. The three remaining top naval powers after WWI - the UK, US, and Japan - all had very ambitious postwar naval expansion plans but reasons to want out of an arms race (the UK was recovering from the war, the US wanted to crawl back into isolationism, and Japan didn't have the GDP to match the other two). At one point the Wilson Administration was proposing a US fleet of 50 battleships and battlecruisers, which fell flat in Congress. The US and UK had become allies during WWI, the UK and Japan had a naval alliance dating back to 1902, and the US and Japan were naval rivals who saw each other as their biggest prospective enemy. The British Empire was somewhat divided on which ally to favor at the 1921 Imperial Conference; in the end they decided to end the Anglo-Japanese Alliance to earn goodwill with the US. The US organized the 1922 Washington Naval Conference to head off British-arranged talks on the Pacific region; by that time the US had cracked Japanese diplomatic codes and therefore knew how far they could push on concessions.
The result was a ten-year "building holiday," the scrapping or disarming of a number of older warships, and a restriction for all future capital ships to a limit of 35,000 tons standard displacement and a 16-inch main gun caliber. That put paid to the US
South Dakota and
Lexington classes, the British G3 and N3 designs, and the Japanese
Amagi,
Tosa,
Kii, and unnamed "Number 13" designs. There were also capital ship tonnage limits/ratios by nation; the US and UK got 525,000 tons each of battleships or battlecruisers as they had global deployments, Japan was allowed to retain up to 60% of their level, and the two smaller signatory powers France and Italy got 35% each of what the US and UK were allotted (a 5:5:3:1.75:1.75 ratio respectively). Cruisers were not limited in quantity, but limited to 10,000 tons standard displacement and 8-inch gun caliber. Aircraft carriers were limited to 27,000 tons and similar tonnage ratios as battleships (e.g. 135,000 tons for the US and 81,000 tons for Japan), with the option to convert up to two existing capital ships to aircraft carriers of 33,000 tons or less (it took some creative interpretation of fine print for
Lexington and
Saratoga to technically meet that limit). "Experimental" carriers or ones under 10,000 tons didn't count towards the limits.
Those restrictions and those of the subsequent London Naval Treaties in the 1930s defined just about every warship designed between 1922 and the late 1930s; this is why USS
Wasp (CV-7) was a cut-down version of the preceding
Yorktown and
Enterprise as the US only had 15,000 tons of carrier displacement left under the tonnage cap at the time. Even the
Iowas and
Montanas were originally intended to adhere to the 45,000-ton "escalator clause" that upped the tonnage limits once other parties (Japan and Italy) withdrew from the treaties in the mid-late 1930s. Between being abandoned by the British and getting a shorter tonnage stick than the British and Americans the Japanese left with a significant chip on their shoulder; that would play into a few quiet little violations (a British naval attaché famously said that if the
Mogami-class cruisers were under 10,000 tons, the Japanese were either building their ships out of cardboard or lying) and their eventual rage-quit of the treaties in 1936. That last bit didn't work out as well as planned; even if everyone's WWII building programs had gone ahead Japan would have built five
Yamato-class battleships versus 11 new British and 17 new American BBs.
There was also a ban on new Pacific fortifications; twenty tears later this made the initial Japanese campaign easier but meant bases like Truk weren't fully developed to support the fleet or repel an attack.