No, US cars are not heavily subsidized unlike China. American auto regulations favor manufacture in America, but not American auto manufacturers. That's why foreign automakers such as Honda, Toyota, Hyundai, Kia, BMW, Volkswagen, Mercedes, Mazda, Nissan, Subaru, and Volvo make cars in America for the American market.
The fact that so many auto manufacturers make cars in the US shows your "make the world reliant on a small handful of corporations and subject to the whims of the US Government" statement to be nonsense.
The rest of your statement is BS. Comparing China to the US is a joke.