What exactly is the US's problem with china??
the same fear that the US will have of india:
1.) we are demographically large, far larger than the US. however, before when we were weak and poor, the US was OK, since it could continue consuming resources like crazy.
2.) when our economies started developing, there was the fear from the US that we'd use more resources, thus depriving it of its stranglehold on consuming an extremely disproportionate amount of the world's resources.
3.) furthermore, these 2 countries with large populations are not only developing fast but started from a low base, meaning that their consumption of world resources is guarenteed to increase!
4.) not only that, both are independent and free of US influence in both foreign and domestic policy. The US cannot tolerate different opinions and independent governments. Note, it is perfectly fine with violations of human rights, brutal dictators, hereditary kings, but never independence. What is Iran? Capitalism + Democracy yet it is demonized by the US. What is Saudi Arabia? Feudal Monarchy that's best friends with US.
5.) the mode of rise is also important. China and India are not rising through selling limited natural resources. China is an industrialized nation (though not a developed one). India is industrializing. The US never fears countries that get rich by selling their blood, but they truly fear other industrial powers, especially those not under their direct control.
6.) India is a part of this too, but India currently is at the stage where China was 15 years ago. When the US is number 2 (in British Empire days) they waited for their chance to strike and become number 1. When the US is number 1, it always links up with number 3 to actively suppress number 2. India should beware.
In summary:
US fears losing its control over resources, fears independent governments, fears alternative values systems, fears countries with superior demographics, fears alternative technologies, fears the spread of non-US controlled technology, and fears most of all, that the "legend" status it tries to cultivate through Hollywood movies and propaganda news is broken.