Comments by "" (@RedXlV) on "USS Maine (BB10) - Guide 220" video.

When the transition to smokeless powder happened, why switch to a smaller-caliber gun? A 12-inch/40 smokeless gun can hit harder than a 13-inch/35 using black powder. But wouldn't a 13-inch/40 with smokeless powder have hit even harder than that? This also would've given the US Navy a potential leg up on the other pre-dreadnoughts, something that should've been seen as useful during a time when Congress was never going to allocate enough money to achieve numerical superiority.
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@stevevalley7835 Mutsu wasn't actually in commission yet when the WNT was being negotiated. Hence she was originally supposed to be scrapped. But she held great importance to the Japanese people (having been paid for with public donations), so they were insistent on getting to keep her. The original proposal was that Maryland and Nagato would've been the only 16-inch armed BBs in the world, at least until the 10 year building holiday expired. In your alternate scenario where the entire Colorado-class were cancelled prior to the treaty, Japan will certainly still insist on getting to keep Mutsu. Most likely this means the US and UK each get to immediately build 2 Treaty-compliant BBs in return for allowing Mutsu to survive.
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