Approximately 140,000 Americans now work in primary steel and aluminum production — down from approximately 230,000 in 2000, according to the Bureau of Labor Statistics. Meanwhile, according to Moody’s Analytics, more than 6 million Americans work in industries that use steel and aluminum to make other products, such as motor vehicles, aerospace, construction and metal fabrication. Economists say some of those jobs could be at risk if the U.S. imposes unilateral tariffs on imported steel and aluminum, since the move would likely drive up input costs for those downstream industries. And millions more American workers might be affected if U.S. trading partners retaliate with countervailing punitive tariffs against U.S. exports.

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