The only real opposition the Chinese face for global economic supremacy are the European Union, which is the only political body with the financial clout to do a little fiddling of their own.
Dude, whatever U're smokin- GIMME SOME!!!

The EU does NOT have economic supremacy over the Chinese or US, and it will fall behind being more and more a nanny state.
Europe will also be a retarded Muslim state in 20 years (look at France today- riots after each criminal killed while running from the cops), excluding countries like Poland, the Czech Republic etc, where there aren't many immigrants from the Middle East.
Another thing is that Europe (maybe except the UK and Poland) tends to be as pacifistic as possible, so don't count on military opposition either.
Besides, no other county should mess with it's 2,25 million army and the old russian buddies. They can easily 'convince' someone to give them food.
I'd like to see them 'convince' India.
BTW- I think it's the 'old russian buddies' that fear China most today- they have future Chinese resources, and if they didn't have nukes, Siberia would probably be a
current Chinese resource dump.
/EDIT: AND they have at least 550 million persons fit for military service, which they probably wouldn't hesitate to use in emergency. PLUS another 660 millions NOT fit for service.
So they have manpower. They also have some modern production tech, thanks to the West.
What they don't have is:
-way advanced weapons (such as a fleet of stealth military planes or tanks with depleted uranium embedded in their armor)
-enough oil (China and India are one of the main reasons of the hellish price of petroleum)
-a way to get more oil other than buying or beginning WW III.
-a growing neighbor-superpower: India, which is a friend of the US.
One more thing- someone wrote that the US is digging their own grave with a shovel made in China by spending so much that the dollar is going down, and US public debt is going up. I think the grave is
for China:
A cheaper dollar is good for the US to export stuff (ie. crappy TV shows, Pepsi/coca-cola, McDonalds etc

). It's also bad for China because the $5 they earn today is worth less than the $5 a few years ago for the same 'Made in China' product. Oil prices are growing, forcing China to spend more cash on it since they need to import a lot and their demand is growing fast.
The US are friends with India, providing alternative cheap labor and huge amounts of manpower, which means that China will be slowed down on their way to becoming a superpower.
The Persian Gulf belongs to the USA, so China can't take the oil for themselves without WW III. In the near future, when Iraq will grow up to stop terrorism on it's own and Iran will be occupied by the US (thanks to their crazy president who won't stop developing his A-Bomb untill it can be used against Israel)- China will be paying US companies for crude. Since Big Oil = Big Tax Money, I doubt the US budget will fail anytime soon.
Summing up- China will need to rely on oil owned by America in the next few years, so they lost before the games even began, and they can't do anything about it.