How much luck have all of you had with the AI doing more or less reasonable things with its navy? In my last game, Germany was by far the top dog. He was funneling troops onto a small continent with Oil, Coal, and Uranium (yet another game, where my continent had no Coal). After a while, I got some destroyers around to the far-side of the continent (Bismark’s side), and proceeded to smash his transports. At the same time, Russia was trying to setup some colonies on my continent, so I declared war on her, and smashed her transports too.
After about 2-3 waves of transports (probably about 3-transports per wave) they both gave up. Catherine wasn’t doing to well, so that may be why she stopped – she ended up trying for a scientific victory, but I beat her too it. Not sure what Bismark was thinking. He built the UN, but never got more than two votes (his own vote, plus his UN owner bonus vote).
After I finished the game, I dropped some nukes on Berlin and Hamburg just for kicks, and discovered that just about every hex on his continent had Mechanized Infantry or Tanks on it. It was almost literally jam packed with troops. But he never built any naval ships at all that I could see, and he stopped trying to invade after I bloodied his transports.
I know the AI is capable of building a navy, the game before that France had a whole bunch of Frigates, most of which he used to beat up on one of my minor nation allies. He could have taken my ally out, except in this case the AI got the city down to one strength, but neglected to bring any troops along to actually capture the city. This probably went on for 100+ turns.
In this last game, Japan had ships and submarines but got taken out fairly early (I started this game in the industrial age). And the barbarians actually had a destroyer at one point. But I don’t think Germany or Russia ever built any ships.
I’m wondering if some AI personalities build ships, whereas perhaps others don’t. That’s the only explanation I can come up with for Bismark’s behavior.