OTL, the US took the Philippines and Guam, but let Spain keep the remaining Mariana Islands, Palau, the Carolina Islands, and the Marshall Islands. These leftover islands were sold to Germany in 1899, and conquered by Japan during WW1, allowing Japan to use them in WW2.
What if the US decided to take these islands as well, to secure communications between Hawaii and the Philippines? Japan would presumably still join the Allies in WW1 to take Tsintao and get other concessions in China, but then what would happen in WW2? This would make it much harder, if not impossible, for Japan to invade New Guinea and the Solomons, and perhaps even the Philippines and the Dutch East Indies. Would Japan still attack the West?
What if the US decided to take these islands as well, to secure communications between Hawaii and the Philippines? Japan would presumably still join the Allies in WW1 to take Tsintao and get other concessions in China, but then what would happen in WW2? This would make it much harder, if not impossible, for Japan to invade New Guinea and the Solomons, and perhaps even the Philippines and the Dutch East Indies. Would Japan still attack the West?