The problem for Japan is that nothing they did in 1941 or 1942 against the Americans would have made a bit of difference. Even if they sank all the American carriers at Pearl Harbour, won Midway, & occupied the Hawaiian Islands, none of that would have made a difference. In 1940, the Americans launched a naval construction programme that guaranteed them naval superiority over Japan by the end of 1943/early 1944, even if all six American carriers in the Pacific had been lost. The new Essex-class carriers & Independence-class light carriers, in combination with the next generation of American naval aviation, (F6F Hellcats, etc.), ensured the Americans naval superiority by 1944 regardless of losses suffered.
Also, I don't think Japan could have taken the Hawaiian islands even if they had wanted to. First, the only amphibious landing they conducted in the Second World War that was opposed on the beaches was Wake, & they lost that the first time. Second, the Americans would have thrown all available airpower in the Hawaiian Islands to hold them, which likely would have been a match for the Japanese carriers. Thirdly, the Japanese themselves concluded in early 1942 that even if they managed to take the islands, they did not have the merchant marine to keep the garrison of the island supplied past three months.
As well, I just don't buy the idea that the US home front was fragile & would have demanded peace if losses continued. In all countries during the war, the home front held up under pressure of losses and defeats. Britain survived the Blitz, Germany survived years of day & night bombing, Russia survived wholesale massacres. I just don't see the Americans reacting all that differently.
Plus, there is another whole problem with the idea of Japan invading Australia or the United States - the Army would never have released that many divisions for overseas operations. They viewed China as the key theatre, even after 1941. I hope HOI simulates the extreme rivalry & disunity between the Japanese Army & Naval commands. The Japanese player shouldn't be able to pick whatever divisions they want & land them at Australia, for example.
Also, I don't think Japan could have taken the Hawaiian islands even if they had wanted to. First, the only amphibious landing they conducted in the Second World War that was opposed on the beaches was Wake, & they lost that the first time. Second, the Americans would have thrown all available airpower in the Hawaiian Islands to hold them, which likely would have been a match for the Japanese carriers. Thirdly, the Japanese themselves concluded in early 1942 that even if they managed to take the islands, they did not have the merchant marine to keep the garrison of the island supplied past three months.
As well, I just don't buy the idea that the US home front was fragile & would have demanded peace if losses continued. In all countries during the war, the home front held up under pressure of losses and defeats. Britain survived the Blitz, Germany survived years of day & night bombing, Russia survived wholesale massacres. I just don't see the Americans reacting all that differently.
Plus, there is another whole problem with the idea of Japan invading Australia or the United States - the Army would never have released that many divisions for overseas operations. They viewed China as the key theatre, even after 1941. I hope HOI simulates the extreme rivalry & disunity between the Japanese Army & Naval commands. The Japanese player shouldn't be able to pick whatever divisions they want & land them at Australia, for example.