Although Trump’s professed goal is to “get a better deal” on trade, his brand of economic nationalism is just one step away from old-fashioned protectionism. The president claimed that “protection will lead to great prosperity and strength.” Yet the opposite is true. An “America first” trade policy would do nothing to create new manufacturing jobs or narrow the trade deficit, the gap between imports and exports. Instead, it risks triggering a global trade war that would prove damaging to all countries. A slide toward protectionism would also undermine the institutions that the United States has long worked to support, such as the World Trade Organization (WTO), which have made meaningful contributions to global peace and prosperity.