"Recycling was supposed to be one of the few positive environmental legacies bequeathed by the boomers"

Slate:

Your 2011-era empty Coke bottle wasn’t just worth a lot because of high oil prices—it was worth a lot because Pakistan had suffered devastating monsoons in the summer of 2010. Flooding in the Indus River was one of a cascading series of events that sent cotton, in April 2011, to its highest nominal price since records began in 1870. Jeans were going to be more expensive, Levi’s announced. And so, it turned out, was recycled PET plastic, because for Chinese manufacturers of articles like teddy bears and blue jeans, polyester fibers made from old plastic bottles were a cost-effective replacement for cotton. Cotton was up; plastic was up; recycled PET prices went up. As when cotton hit its previous high price in 1995, the scramble was on for old bottles. Which you, American reader, the world’s leading consumer of soda and bottled water, had in spades.

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Relatedly, the explosion in Chinese exports meant that ports like Los Angeles (the nation’s largest) were always stacked with containers that arrived full of new sneakers and televisions but often had to return empty. Which meant shippers would basically take old paper and cardboard back to China for free—it functions as ballast. As a result, shipping a ton of old boxes from Los Angeles to Hong Kong was often cheaper than shipping it to a recycled paper mill in eastern Washington.

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Then came National Sword. It didn’t come out of nowhere. In 2013, Chinese President Xi Jinping announced Operation Green Fence, a crackdown on poorly sorted shipments of used paper and plastic that arrived from America contaminated with trash. The work of sorting those bales had fallen to Chinese families whose impoverishment and appalling working conditions were the subject of the 2016 documentary Plastic China.