The Chinese worker loses because instead of participating in a functioning labor market (like the ones in US, most of Latin America, East/West Europe, etc) his only choice is slave-like factories. The US worker loses because he loses his job. "The consumer" is the same as the US worker, so under this scheme everyone loses, except a small cartel of US corporations and local elites in some developing countries.
The point is not to restrict the international labor market, but to free it from this artificial pipeline that is only possible because US corporations work together with local elites in countries like China to suppress their local labor markets.