Never miss an opportunity to pitch good books
Really good overviews of the Pacific war are H.P. Willmott's books, IMO.
Empires in the Balance: Japanese and Allied Pacific Strategies to April 1942
This is Willmott's overview of rationales for fighting, and strategy. Another good one along those lines is
Combined Fleet: Decoded by Prados.
These include the larger political picture.
Clearly Japan was in the wrong. While you can argue they felt "forced" into war, they were only forced in the sense that they would not ever stop their atrocities in China willingly. Some will say our colonialism in asia was no better, but they'd be forced to jack up our body count by a couple orders of magnitude to make that claim.