Well, the Japanese built the ultimately large battleships. However, the Americans were the ones with the second largest.
Germany's Bismarck and Tirpitz were excellent ships as well, and so was the British King-George class.
In an engagement betwen giants of these types the sheer size does not say all, for the first salvo to score a hit is often crucial.
The Bismarck had about the equal firepower with its 15 inch guns as HMS Hood, but Hood receving a direct hit into its magazines went up in one BOOM. However, HMS Nelson(or was it Rodney?) was the first one to score against Bismarck, knocking out its fire control with a single 16 inch shell, - Bismarck failing to score any hits after that.
If we were to get some of these giants into AH one day, I guess the damage model would have to be reviewed;)
