Yes you can invest in core business. You can come here and start a corporation. If you want to borrow money, the government will GIVE it to you to start a business (they also like to take part of your profits, but that's not news. Sounds pretty fair, no?)
Seriously, I am not sure if "foreigners" can buy stock directly, but land ownership is not prohibited.
Sorry - that's not what I mean - venture capital is surely one of the things I admire in the US economy - you guys have experts for that - our bankers are a bit trashy - one day they burn cash like mad, next day the inventor of the perpetuum mobile would be send home because they wouldn't see a market for that product.
What I was referring to is, that the chineese are unable to buy for example pfizer or united technologies for their huge ammount of dollar debts they hold.
So the chineese get dollars but certainly not the freedom to go shopping for what they desire.