"In the 19th century, Britain profited immensely from smuggling opium into China. When China decided to ban the material to save its population and economy, the British launched the Opium War, which started a century of humiliation for China." [1]
"China is currently the primary source of the precursor chemicals needed to manufacture fentanyl." [2]
"Fentanyl is many times more powerful than heroin... between 2019 and 2021, the opioid killed 200 Americans a day.
...
It seems most likely that the fentanyl crisis began without the Party's knowledge, and that China's leaders ... are simply allowing the development of a situation which happens to appeal to their sense of historical justice." [3]
[1]
http://us.china-embassy.gov.cn/eng/dshd/202209/t20220930_10775097.htm
[2]
https://theconversation.com/what-the-opium-wars-can-tell-us-about-china-the-u-s-and-fentanyl-247170
[3]
https://quillette.com/2023/06/14/the-reverse-opium-war