Agreed. Started reading it and am just into "From Poland to the Pacific".
The only quibble I have with him is that if Japan hadn't attacked Pearl Harbor and the Philippines, the U.S. would have stayed out. Everything I have read about that time was that Japan worried that if they didn't take out the American fleet, their flank would be open to attack when they went into the Dutch East Indies. They felt they HAD to attack, counting on quick victories and then a negotiated peace giving them hegemony over the area.
Then they screwed up their timing of the Declaration of War.
At that point the Japanese were as committed to their overall plan of the Greater East Asian Co-Prosperity Sphere as the Nazis had been to lebensraum - the commitment that had, despite all good sense, impelled Hitler to attack Russia when Stalin was already happily selling him all the oil he needed. You might say - this is my conclusion, not Hanson's - that it was too much of a commitment to ideology that trapped them both into continuing the plans that eventually doomed them.
You suggest that the U.S. might have accepted the new status quo if the Japanese hadn't gone ahead with Pearl Harbor, and I agree (so does Hanson). Hanson further states that if they had stopped short of Singapore, the British might have done the same. Call it hubris. The Japanese plan was to engage the U.S. Navy in a giant surface action as they had the Russians in 1905, and we simply wouldn't give that to them.