Scaling the F3 study toward the available treaty tonnage could produce a very fast British battlecruiser, especially if a 15-inch/50 armament saved weight.
New British battlecruisers could make Renown and Repulse available to Australia and New Zealand, spreading cost while maintaining fast ships in the Pacific.
Carrier displacement alone does not determine aircraft size because engines, aircraft design, lifts, and hangar arrangements remain independent constraints.
Repeated two-ship and one-ship orders would turn the 1920s into a design sequence, preserving gun production and feeding lessons from each class into the next.
The four Kongōs remain treaty-eligible, affordable scouting ships whose numbers and operational role outweigh the attraction of replacing them with fewer, larger hulls.
The 9.2-inch ceiling reflects the upper end of proposals actually discussed, while American negotiators still seek the largest practical gap between cruisers and capital ships.
Italian battleships combine speed with substantial protection because their geography demands rapid manoeuvre inside the Mediterranean followed by a hard fleet engagement.
Operating mainly in waters similar to the test environment reduced one source of torpedo failure, though Atlantic submarine operations still exposed problems.
Because Congress has already funded them, the United States is likely to complete a fourth Colorado and five Lexington battlecruisers rather than start fresh programmes.
Five Lexington battlecruisers give the slow American battle line a fast arm designed for reconnaissance, economic warfare, and independent support rather than equal-line combat.
In 1922 the carrier remains an experimental type, while Congress and the navy already understand the intended role of the funded Lexington battlecruisers.
Fast British and Japanese capital ships would expose the 21-knot American battle line and make a historical 27-knot Yamato an inadequate answer to the new environment.
If capital-ship construction continues through the 1920s, a later treaty may regulate replacement and light carriers instead of imposing the historical naval holiday.
Continuing naval orders could support employment and technology through the Depression, but the political coalition that brought Hitler to power cannot be reduced to economic conditions alone.
Extra displacement could bring Implacable- and Essex-scale capabilities forward while leaving Britain protection-heavy and America aircraft-heavy in their design choices.
American negotiators could rationally expect superiority to deter war while overlooking how the same imbalance might make Japan frightened and more willing to take dangerous risks.
More and larger carriers could make Taranto far more destructive, while a Japan invested in the treaty system might pursue partnership with Britain rather than the Axis.
A larger Illustrious and the possible survival of Glorious could turn Taranto from a small specialist raid into several waves of torpedo and dive bombers.
A Japan that sees the treaty order as beneficial could invoke the memory of its British alliance and enter the European war against Germany and Italy instead of joining the Axis.
A USS United States conversion can provide the practical bridge to larger purpose-built carriers; without it, the navy must climb through more incremental designs.
Without wartime pressure, American politicians might have funded battleships while postponing carrier and wider fleet modernization until the late 1920s.