USA exports are idling around 1/4 to near 1/3 of the GDP. Our economy is heavily tied to imports from other counties.

When it comes to isolation I think of this:

    The word invasion itself is a good example of this.

    A French ironmaster says: "We must protect ourselves from the invasion of English iron!" An English landlord cries: "We must repel the invasion of French wheat!" And they urge the erection of barriers between the two nations. Barriers result in isolation; isolation gives rise to hatred; hatred, to war; war, to invasion. "What difference does it make?" say the two sophists. "Is it not better to risk the possibility of invasion than to accept the certainty of invasion?" And the people believe them, and the barriers remain standing.

    And yet, what analogy is there between an exchange and an invasion? What possible similarity can there be between a warship that comes to vomit missiles, fire, and devastation on our cities, and a merchant vessel that comes to offer us a voluntary exchange of goods for goods?