A-150
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At the National Interest, I write a bit about Japan’s abortive A-150 class battleships:
Japan ordered two A-150 battleships in the 1942 construction program. The first would have succeeded HIJMS Shinano on the dock; the second, the never named fourth sister of the Yamato class. However, wartime demands for smaller ships (and eventually for aircraft carriers) meant that neither ship was ever laid down.
But the war only exposed underlying economic realities; it did not forge them. Japan barely had the industrial capacity to build the initial Yamatos, along with all of the support ships that the battlefleet would require.