Why a 1938 Anglo-American fleet swap breaks British global coverage

What if every British and American battleship and cruiser, including ships under construction, swapped navies in 1938?

Britain receives useful hulls but the wrong fleet mix for global commitments, producing severe cruiser and speed gaps and an urgent British building program.

The 1938 fleet swap changes the fit between ships and national commitments. Britain could employ slow American Standard-type battleships on convoy and station duties, but replacing its modernized battleships and much larger cruiser force would disrupt global coverage. Hood, Renown, and Repulse remain British under the literal wording because the question names battleships and cruisers but omits battlecruisers. The clarification that ships under construction also transfer then removes Britain's King George V programme and brings the North Carolinas into the exchange. Those fast battleships are useful, but their small number does not fill every gap. Both navies would need to adjust ammunition production and logistics, while Britain would have a strong incentive to accelerate replacement cruiser and Lion-class construction.