IOTL, the first armed submarine was designed as a submergable torpedo boat. This may seem a bit "out-there," but what if they were designed as regular warships, but able to be submerged-basically, instead of torpedoes as primary armament for subs, guns would be the norm. Hence, we'd see submergable destroyers/cruisers/battleships/ETC. If this is even remotely possible, how would it affect the world's navies and the development of warships?