Lexington's precise tonnage claim damaged American credibility

Their large battlecruiser hulls became highly capable carriers, but conversion pushed them beyond the 33,000-ton exception even after adding the permitted 3,000-ton protection allowance. British and Japanese naval architects could estimate machinery, dimensions, and component weights well enough to question an exact 36,000-ton declaration. Openly admitting a small overrun would have been less damaging than a suspiciously perfect figure. Transparency could have produced a limited reciprocal concession, perhaps a little more British carrier tonnage, while establishing an expectation that later overruns should also be declared rather than hidden.