The exercise sets an explicit horizon instead of projecting a single alternate timeline indefinitely. It traces consequences through the First World War and the Washington Naval Treaty era, roughly to 1925. Beyond that point, aircraft and other technological changes create too many interacting possibilities for a confident forecast. The limit separates bounded strategic deductions from later possibilities that remain open.
Notable Point · 9:06-9:45
Why the forecast stops around 1925
Detailed prediction stops at about 1925 because aircraft and other emerging technologies multiply the counterfactual's uncertainty.