The 1936 agreement had weak strategic value because Japan and other plausible opponents were outside it. Britain, the United States, France, and the Commonwealth states were therefore limiting navies that were increasingly unlikely to fight one another. The comparison with a modern alliance voluntarily banning a useful weapon shows why external restraint was missing. In this reading, treaty membership matters as much as the numerical limits written into the text.
Chapter · 3:26-5:42
Why the 1936 London treaty lacked deterrent value
With Japan and other likely opponents outside the agreement, the principal signatories largely restricted navies they were unlikely to fight.