How permissive destroyer limits would enlarge every navy's designs

What would major navies build if treaty destroyers could be as large as French contre-torpilleurs?

Britain and America would enlarge their leading destroyer types, while Japan and Italy could approach light-cruiser size under the destroyer label.

Britain would likely produce an enlarged Tribal-type design, while the United States would scale up the Fletcher concept. Japan could exploit the category until its nominal destroyers resembled light cruisers. Italy's answer might resemble a slightly reduced Capitani Romani class. The treaty label would therefore cease to describe a common tactical size and become an incentive for competitive growth.