428 pages, (456 counting notes, index, and bibliography.) My Dad got this for me at at garage sale, and I'm glad he did. Hagen covers such things as bios of Pappy Boyington, Curits LeMay and Masaharu Homma, and places like Chungking, Rabaul and the Marco Polo Bridge. He also touches on Unit 731 at the end, and the Comfort Women, in much appalling detail. I enjoyed his chapter on Admiral Nimitz and in contrasting his more low-key style of command with MacArthur's flamboyance. He also talks about whether FDR "Knew" Pearl Harbor would be attacked, and places blame on the services deciphering units for jealously guarding what they had deciphered instead of sharing it with the other people who should know. He certainly tried to cover a lot, and I'd have liked more detail on some things, but he did a good job overall. You might enjoy it.
Think of those books as a Wikipedia/encyclopedia for the Pacific. They are a place to start & pique your interest, but it is up to you to look for books that have far more depth on a particular subject/aspect of the Pacific.