Naval treaties and tolerated evasion

Foreign navies photographed Japanese cruisers beside their own ships and could estimate that the declared figures were too low. They nevertheless had incentives to tolerate discrepancies because every signatory had exceptions, favorable interpretations, or evasions it preferred not to advertise. A contemporary analogy sets disputes over China's South China Sea island-building against the British-American position at Diego Garcia and Mauritius's claim, suggesting that strategic utility shapes which breaches states choose to enforce. Remaining inside the system required all parties to preserve the appearance of restraint and gave naval ministries a convenient foreign benchmark when arguing for funds. Japan's withdrawal changed that political bargain by activating escalation provisions and freeing the other powers to respond openly. Arms-control rules served a political function that went beyond their tonnage limits.