How treaty navies escaped the 10,000-ton cruiser rule

Other treaty powers escaped the cruiser limits through Italian, German, and Japanese creative accounting or US designs that soon paid little more than lip service to the original limit.

Question

Did other treaty powers arrange for extra cruiser armour or weight to appear once war began?

Short answer

Yes, but by different methods: Italy, Germany, and Japan used creative accounting, while later US cruisers largely outgrew the original 10,000-ton concept.

Notes

A viewer asks whether navies besides Britain arranged for heavy armour to appear once war made treaty compliance irrelevant. Italy, Germany, and Japan relied on creative accounting instead of a single common method. Late-1930s and early-1940s US cruiser construction took another route, with ships entering service that bore little relation to the original 10,000-ton ideal. Some navies obscured figures, while others allowed later designs to outgrow the nominal category.