President Donald Trump has given Canada until Friday to sign on to a new trade agreement replacing the North American Free Trade Agreement. Monday, Trump announced that the United States and Mexico already had a new pact.

Among the most intensely negotiated issues still on the table is Canada’s protected dairy industry. The government tells farmers how much milk Canadians are expected to drink and how much cheese they’ll eat, and that’s how much is officially produced. To further avoid a surplus, Canada sets tariffs on imported milk at over 200 percent.

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