Treaty carrier tonnage reflected a sea change already underway

Was interwar carrier construction driven only by treaties, or was a broader sea change already underway?

A broader change was already underway; the large treaty allowances themselves show that navies were taking carriers seriously before their final form was known.

The treaty system shaped the carriers that navies built, but it did not create interest in the type from nothing. Governments wrote very large carrier allowances into the Washington settlement while the mature design and doctrine were still uncertain. Committing 135,000 tons each for Britain and the United States signaled that the powers expected carriers to matter. The construction boom reflected an institutional and strategic shift already underway alongside the opportunities and limits created by treaty rules.