In a Wall Street Journal interview last week, President Trump said if he were to “terminate” the North American Free Trade Agreement, it “would be frankly a positive for our country.”

This bluster could be a negotiating ploy before the next trilateral Nafta talks, set for Jan. 28 in Montreal. If not, Mr. Trump should stop threatening. Withdrawing from Nafta would immediately kill American jobs, while handing Democrats the midterm elections on a silver platter.

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