What a 10-inch treaty cruiser would change

What might a 9.5- or 10-inch-gun American treaty cruiser look like?

It would probably be a roughly 15,000-ton cruiser, with its larger guns also pushing treaty powers to preserve a four-inch calibre gap before capital ships.

Gun-calibre limits formed a connected treaty system. A 10-inch cruiser would probably need a displacement ceiling around 15,000 tons. Treaty negotiators wanted clear water between cruisers and capital ships, partly to keep nominal cruisers from serving as auxiliary battleships in the battle line. A higher cruiser ceiling would push the minimum capital-ship calibre toward 14 inches and could encourage an 18-inch upper limit. Changing the cruiser category would therefore reshape the treaty fleet as well as producing a larger heavy cruiser.