China + USA ! My dream team of capitalist world domination! Muahahaha!
China + USA will win against the world because
China + USA 's steel production makes up more than 50% of the world.
China's manufacturing capability + US technology + Chinese manpower + US air bombing = World having less industrial capacity to build tanks and planes than China and USA because of Chinese manufacturing capability and the bombing of world factories.
If I am the Combined Force Supreme Commander (USA+China), I would command the combined forces to invade and defeat one nation at a time.
1. Joint US-China invasion of Russia. China invading from Manchuria and US invading from Alaska. The combined force meet in Siberia. Pre-emptive strike on nuclear capabilities before the invasion. The defeat of Russia would secure China northern flank.
2. Invade Korea and Japan next.
3. After the 3 big military power Russia, Japan and Korea is defeated. The easy states will be next to go and that is South East Asia(for resources also)
4. After South East Asia is secured, Australia next to capture its uranium production.
5. Countries to the China's North and South is defeated. India will be next to go, and then Pakistan, and then Iran, and then towards Middle-East. By this stage, Europe would have concentrated most of its military power in middle east as the fall of Miiddle East will ultimately means the defeat of the rest of the world. Of course European military simply cannot handle the thousands of F-22's and 15,000 M1A2's (jointly produced by China + USA) and thousands of AH-64.
If USA outsource to China all of its high tech hardware. No way the world can win.
For the opposition- other than Europe and Russia, the rest of the world simply do not have the combination technical know-how and mass manufacturing facility to mass produce high-tech hardware such as F-22 or M1A2 for example.
The rest of the world might have more economic power. But with US+China's concentrated attack, it is almost impossible to defend the thrust of double superpower attacks. If the rest of the world is concentrated in a small continent like Australia and they have to fight US+China. Then the double-superpower will have problem