EDIT: to clarify, there are also examples where increased foreign industry will benefit America. For instance, if Kuwait doubles its productivity, oil imports to the U.S. will be much cheaper. But my point still stands that this is not also the case. Increased productivity from other countries can be positive or negative to America, depending on the specific situation.
Free-trade policies tend to be most beneficial to the market incumbents; but I would note that even when a foreign company simply comes in and exploits cheap labor, the workers will get better wages, and even if that doesn't directly benefit their own lives, it can give their children a better lifestyle and education.