A strike-carrier category solves the conversion problem

The historical treaty permitted only two unusually large carrier conversions, while this scenario requires three for both Britain and the United States. A special strike-carrier category gives those navies three large conversions each and Japan two. Ordinary carriers remain smaller, though their limit must be high enough to avoid a severe capability gap between converted and purpose-built ships. These rules determine whether Courageous, Glorious, and later purpose-built carriers still make sense within each national allowance.