Widespread 18-inch battleships would reduce the attraction of rebuilding Italy's older 12-inch ships in this counterfactual. New construction would require larger hulls, dockyards, and budgets. A further increase to 20-inch guns is judged unattractive because of the loss in rate and volume of fire. Eighteen inches is therefore proposed as the practical upper limit in this assessment, rather than an absolute engineering boundary.
Notable Point · 3:01:24-3:02:07
Larger guns, larger docks, and the cost of slow fire
The counterfactual links larger guns to industrial costs and judges 20-inch weapons too slow to justify their greater calibre.