Two K3s undermine American treaty assumptions

Would two operational K3s collapse the basis of the American treaty proposal?

Yes. They would prove Britain could build the new generation and make the historical restrictions and ratios difficult to preserve.

American negotiators historically underestimated Britain's willingness and ability to sustain construction. Britain nevertheless used its interwar treaty allowances more consistently because it remained willing to spend heavily on naval requirements. Two completed K3s would remove the assumption that London could be pressured into abandoning the new generation. They would enlarge the capital ships permitted to other powers, alter the ratios available to Japan, and require investment in worldwide docks and bases capable of supporting them.