My opinoun:
- Without US help at all, Japan will lost the war with China. Because China can cut the oil route/ import export route disrupt sea lanes of all ships to and from Japan using subs. China has her own GPS system. China missiles are accurate. China has land base missiles that can attack Japan main island directly. Therefore Oil tanks/reservior and electric power plants and all building in Japan are at risk. While Japan may have the same ability to attack China main land, she lacks the ability to cut China oil import/export. Japan Chance become win 0 lose 100%. Japanese cities bombs, large number of japanese died. China also get her cities bombs. Casualty of Japan > China.
- With US help on intelligence but not war directly. Japan Chance with PLA navy is much better. However, China can still use submarines,DF21D to attack tankers coming to/from South China Sea. Japan pacific ocean side could be save for import export. Japan pacific ocean side could not be save for import export. This depends on whether Japan can destroy all PLA navy submarines or not. Pacific Ocean is very large. Therefore, submarines has better chance of survival in the mid of the ocean. I guess Japan Chance become win 30 lose 70%. Casualty of Japan > or = China
- With full US help,
US. will wait until Japan is exhausted, bombs, destroyed like the previous scenario ( very likely ) before play her hands. US will need to destroy China's mainland asset, like radars, Satellites command & controls, rockets launching platforms, etc. Space assets of both side will become the very very first among being attacked, Perhaps even before declare war. China will retaliate to US mainland by ICBM, Sub Launch Ballistic Missiles. If things develop to this position, no body know when the first Nuke will be used. But then finally Nuke exchange occurs. Now its a question of whose Nuke is stronger, and who can produce Nukes in war time. Anglo group will help US. It is very likely that China will lost, and the end of Chinese civilization/ Chinese as people on this plannet earth. Before China died, she will drag Japan together by Nuke all Japanese cities. Japan will also end/ wipe out from this plannet earth. US now very bad shape. Some of her population survive by migrate to Canada or Mexico but her ability to fight a single war will not survive.
Russia, India are the winners.
Now, with Anglo power weaken, Germany will be free and start building up armies. Why? Because Russia is now sole super power with her land untouched. Her strong neighbor China wiped out. Russia is very likely to take this chance to end Anglo dominance because there is only one strong country of Anglo left: England. Germany will have to think really hard whose side will be the best. Who ever win this battle between Russia/Germany/England/Canada will be the next superpower until WW4.