“Tremendously important” is how rancher Coleman Locke describes the role of international trade to his cattle business. But now he is gearing up for a new threat – the potential loss of trade deals that could cut off a huge slice of his ranch’s yearly sales. “In 2016, 25% of the breeding stock that we sold here at this ranch went out of the United States, it’s a tremendously important market for us,” says Mr Locke. He’s not alone. Last year the American beef industry earned over $6bn (£4.9bn) from overseas sales. Among the biggest purchasers are Canada and Mexico, partners with the US in the North American Free Trade Agreement (Nafta). President Trump’s promise to renegotiate Nafta and possibly place tariffs on Mexico or other US trading partners has the industry worried. “Nafta is extremely important to us. It’s one of the biggest trade deals that agriculture has ever had,” says John Robinson from the National Cattlemen’s Beef Association (NCBA). The beef industry is already reeling from the loss of the Trans-Pacific Partnership (TPP), which President Trump withdrew from in his first week in office. The free trade agreement with Pacific Rim countries, including many in Asia, was set to expand America’s export market for beef. By some estimates, it could have added $400m in sales each year.