For those who never had any economics or are in high level policy positions, an over-valued dollar has an enormous effect on the balance of trade. If the dollar is over-valued by 20 percent it has roughly the same impact as imposing a 20 percent tariff on all U.S. exports and providing a 20 percent subsidy on imports. There is nothing in policymakers' bag of tricks that can come close to having the same impact on trade as a reduction in the value of the dollar. Anyone who argues otherwise (think of people pushing the TPP or TTIP) are either showing their ignorance or not telling the truth.
