I have to write this in small sections, since time is kicking my butt right now.
At the start of the Meji Restoration, Japan came out of centuries of self-imposed isolation under the threat of cannons from the US. The display of naval power by Perry and the letter from the US president were threats to either open up for US trade or risk being colonized as other nations throughout Asia had been.
Japan sent people around the world to study the world power structure. It did not want to be relegated to a colonized nation and ended up adopting Britain as a model. - a small, island nation with limited resources, a vast empire of colonies to provide resources, a long cultural history and a monarch with a parliamentary form of government.
Even today, Japan carries over these similarities in daily life. Japan drives on the left, has the same style of government and office hierarchy and organization is based on the English shipping insurance business from the late 1800s, as witnessed by Japanese visiting England at the time.
Japan had to either gain colonies or be colonized as China, the Philippines, Burma, India, Vietnam, Cambodia, Laos, even Midway and Hawaii, had been by the English, Dutch, Portuguese, French and the US. (The colonization of Hawaii is an interesting case study about patience and political influence that business has in US foreign policy.)
MacArthur was in the Philippines because it was a US colony and thousands of US soldiers, and many more thousands of Filipinos, died in the US fight to keep the Philippines from declaring independence from the US.
British and US companies were in control, or gaining control of many of Chinese resources and exports.
to be continued...