Replacing a battleship lost during the treaty period

Could a navy replace a first-line battleship accidentally lost in the late 1920s?

Yes, within the treaty rules. A British replacement might continue the Nelson and Rodney design, although the apparent accident could damage the navy's reputation.

The follow-up asks whether an accidental loss in the late 1920s would allow a navy to build a replacement battleship. The answer accepts replacement under the treaty rules, with a British ship potentially continuing the Nelson and Rodney design depending on the date. The increasingly convenient disasters imagined for older ships are counterfactual jokes, not descriptions of actual losses. Another participant raises the reputational cost: an accident that permits a new ship can also make a navy appear incompetent. Replacing the hull would therefore leave an uncomfortable explanation for the loss.