The Japanese path begins with Kaga-class ideas rather than simply copying Nelson. Removing one or possibly two twin turrets, moving toward triple mounts, and reallocating saved weight to armor could preserve a nine-gun broadside inside the treaty limit. Holding speed near 26 knots would make protection against the ship's own guns more plausible. The exchange also cautions that armor may stop an initial hit yet be weakened enough for a later strike nearby to penetrate.
Notable Point · 22:02-24:10
Japan's Kaga-derived post-Washington battleship
The Japanese branch of the treaty counterfactual turns Kaga-class ideas into a better-protected 35,000-ton ship with fewer turrets and a nine-gun battery.