The United States generally had a coherent reason for each 8-inch cruiser class when it was ordered, yet that doctrine changed substantially from the 1920s into the late 1930s. Japan kept a more consistent expectation of reconnaissance, screening, and battle-line support. Its ships never fitted all of those duties comfortably. The two navies therefore faced different problems: instability in doctrine for the United States, and inconsistency between doctrine and design for Japan.
Notable Point · 52:26-53:38
American cruiser doctrine changed while Japan's stayed consistent
The two navies reached different kinds of incoherence: the United States repeatedly changed the role of its 8-inch cruisers, while Japan kept roles its designs could not satisfy.