Adam Smith may have left us a nice homely with his illustration of free trade benefits (selling nails to Portugal in exchange for wine). And there certainly is an element of truth in it. Exchanging goods and services with others DOES bring benefits to both, domestically and internationally.
But one can take this doctrine too far. When societies that are on a completely different level of development are suddenly brought into the pictures (China, India etc) one cannot allow them to compete on an unconstrained basis and accept them as equals in the marketplace.
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