The illicit fentanyl that kills tens of thousands of Americans a year is largely produced from Chinese chemicals cooked up in clandestine Mexican laboratories, according to U.S. authorities. This requires drug traffickers to transport the necessary chemicals halfway around the world. But cartels have found a clever way to smuggle these chemicals from China to Mexico – by first importing them into the United States.

(First, by shipping small boxes inside larger boxes, like we get all the time, but in addition,)

The de minimis rule exempts low-value parcels from taxes, duties and stringent customs reporting rules. It’s meant to keep U.S. Customs and Border Protection from wasting time and effort when the cost of collecting tariffs on cheap imports exceeds the revenue gained. Over 4 million a day.

President Joe Biden, who’ll leave office in January, recently moved to slash the number of Chinese goods eligible for de minimis and require more information about parcels entering through this streamlined channel.

But the process could take months, if not longer, meaning the implementation of these proposals would likely depend on his successor.