America can go to the South China Sea. Why can't China send a fleet to the United States?

First of all, the most basic common sense is that the South China Sea is not ours. Like other non-inland seas, most of the South China Sea is high seas, so everyone can sail freely on the high seas. Secondly, what you call the United States can obviously only be the high seas dominated by the United States overseas, but not the territorial waters of the United States, because territorial waters are within the scope of sovereignty, and entering other people's territorial waters is like violating territory. Finally, it is common sense that the United States is the most powerful navy in the world. They are the only global combat navy, and they can fight anywhere. Our navy's activity ability is very limited, not to mention that it is difficult to maintain normal navigation supplies even in such a long-distance support operation. As a result, only a few garbage ships in the eyes of the US Navy can reach the offshore of the United States, and they are monitored by countless US and its allied navies and even air forces on the way. When you arrive in the United States, you only need to be accompanied by the Coast Guard. In the end, I was bored, wasted a lot of manpower, material resources and financial resources and got nothing, but gave Americans ready-made evidence of China threat theory.