This isn’t the first time we’ve tried to go America First. The last time helped blow up the economy and our relationships with our allies.

This episode was produced by Amanda Lewellyn, edited by Jolie Myers, fact-checked by Laura Bullard and Travis Larchuk, engineered by Andrea Kristinsdottir and Patrick Boyd, and hosted by Noel King.

Transcript at vox.com/today-explained-podcast

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Canadian and American flags flying on the Canadian side of the Ambassador Bridge in Windsor, Ontario. Photo by GEOFF ROBINS/AFP via Getty Images.

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