In 2013, the US food conglomerate Smithfield Foods – the country’s largest pork producer and maker of the famous holiday ham – was sold to a Hong Kong-based company called WH Group in a deal worth $7.1bn. It was the largest ever Chinese acquisition of an American company; virtually overnight, WH Group, formerly called Shuanghui International, gained ownership of nearly one in four American pigs. Such a huge business deal did not go unnoticed; news coverage and an eventual congressional hearing questioned the sale with a mix of good, old-fashioned American xenophobia and reasonable concern for the nation’s food supply. But in the eyes of most people, and certainly most American consumers, the Smithfield Foods sale remained just that: a one-off business deal, if they were aware of it at all.

For Nate Halverson, a journalist with the Center for Investigative Reporting (CIR) out of Emeryville, California, the Smithfield deal was the first point in a much wider and concerning pattern – though the company’s CEO, Larry Pope, assured Congress that the Chinese government was not behind WH Group’s purchase, Halverson found evidence to the contrary on a reporting trip to the company’s headquarters: a secret document, marked not for distribution in the United States, detailing every dollar of the deal, and the state-run Bank of China’s “social responsibility” in backing it for “national strategy”.