Am enjoying the book Shattered Sword, as recommended by several Lexicans. It is about the Battle of Midway, with many previously unseen Japanese sources.
And I enjoy playing historical “what ifs” – while futile of course (an Army Sgt told me years ago “If a bullfrog had wings he’d fly” – but still, what I find fascinating about history is that frequently there are such profound consequences that turn on one individual.
Reason I mention this is that there is a passage in the book that describes Adm Yamamoto, and a political rival of his, Adm Nagano.
Both had solid tactical reasons for pursuing what they did – Yamamoto for attacking the US at Pearl Harbor with the reasoning that if Japan was to have success in the Pacific, they had to knock out the US Navy.
Nagano had an equally good reason for not attacking Pearl Harbor and drawing the Americans in – reasoning (correctly I think) that if Japan didn’t provoke the US, Roosevelt would have had a difficult time bringing the US into a war with Japan.
Speculation is always futile in dealing with alternative history, but it is interesting to think what the Pacific would have been like today had Nagano’s views prevailed.
The Lexicans 
Good read that book. It is very illuminating to see the truth that Yamamoto was not some sort of super-genius, but rather quite the opposite. His having a stompyfeet tantrum over getting his way for Operation MI being just one example. As well as seeing how the staff work prior to the operation was so bankrupt as to be worthless. Ignoring your own wargaming guys is not helping, fellas.
Bill, the US was shot full of luck at Midway.
I would welcome a retelling of the US side of Midway to the same level of detail in Shattered Sword. There is still a lot of myths and cover-ups. Like – where was the Yorktown Air Group?