Isolationism is the typical American answer, and it has proved time and again that America can't handle it. Believe it or not, America exports goods, and those goods play a significant role in our pseudo-imperial economy. The problem is, if you put up protective tariffs, foreign nations put them up as well to spite you, and both sides lose.
As technology develops futher, manufacturing and other services will be eventually replaced by machines, rather than cheap workers, this is an inevitibility that isolation can't stop.
Foreign money invested in lesser developed countries is highly beneficial to them no matter how little, it adds surplus money to their economies, encourages entrepreneurship, and will eventually raise the standard of living in those countries, at which point, the foreign interest will cease, as the workforce demands higher wages and has other oppurtunities for jobs should they not meet those demands.