Which are the most patriotic U.S. car makers? By Donald Trump’s apparent measure, Tesla, BMW and, yes, Ford are the improbable medalists.

The President Elect’s tweets damning auto makers that build factories in Mexico have sent a chill through Detroit. Having focused his ire mainly on Ford last year—and taken credit for a reversal of its plan to build a new plant south of the border--Mr. Trump has this year broadened his attack to include General Motors and Toyota.

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