How treaty limits shaped carrier armor choices

How would British, American, and Japanese carriers have changed without treaty size limits?

British carriers likely would have combined larger air groups with existing protection, while American and Japanese ships probably would also have added some armor.

Treaty displacement limits forced carrier designers to trade aviation capacity against protection. Mediterranean operations made armor especially valuable to the Royal Navy, so an unconstrained British design would probably grow to carry more aircraft while retaining its protective scheme. The American case is less certain because U.S. designs tended to protect the hull while leaving aviation spaces outside the citadel. Even so, both American and Japanese designers probably would have added at least some armor if size were unrestricted while preserving their emphasis on air-group strength.