Thinking deeply in the concept, constructing 10 or 12 of these supertanks by the cost of a battleship has more sense, as they can only be destroyed by enemy fire by direct impact of a heavy calibre armor-piercing gun shell or heavy aerial bomb, and this supertank presents a smaller target than a battleship in the sea. Also, contrary to a heavy cruiser or battleship, it cannot be sunk on land, so the crew can manage to escape or can be rescued if supertank is disabled on enemy territory. Compared to a sea ship, the land ship worth his price!