Diversification is the polite way of saying that America’s friends and allies believe we have become an unreliable partner, and they are now looking elsewhere. From Ottawa to Brussels to Seoul, our trading partners are fed up with the Trump administration’s tariffs, and they have given up on trying to charm President Trump or persuade him that free trade is good. To reduce their economic dependence on the United States and their exposure to a potential global trade war, they are forging trade deals that leave us out of the picture altogether.

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The president may want better deals to replace the old, “terrible” deals he doesn’t like, but so far, the rest of the world has been reluctant to negotiate new agreements with the United States. The long and growing list of tariffs, particularly those based on dubious national security grounds, has weakened the administration’s ability to form coalitions with other countries to tackle legitimate concerns, especially China’s unfair trade practices.

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Regrettably, this leaves the United States on the margins as the rest of the world builds a new trading structure without us. Our workers, farmers and companies will be locked out of important markets. We will lose our chance to help write the rules and set standards for trade in advanced technology, such as alternative-fuel vehicles, 3-D printing and artificial intelligence. Global and regional supply chains will increasingly bypass the United States. And years of efforts by the United States to curb China’s unfair trade practices will lose critical international support.