Number 13 differed from giant-ship proposals that existed only as drawings. Japan had to plan ahead because building and maintaining ships of this size required larger yards and supporting infrastructure, and that preparation was already underway. The comparison with German wonder-weapon proposals makes feasibility a question of maintenance capacity and investment as well as spectacular specifications. Japan could have built the design after a further expansion of its industrial base.
Notable Point · 5:22-7:14
Industrial preparation made the design plausible
Japan was planning the yard and maintenance capacity for Number 13, making it more than a paper super-battleship.