And what most of the public doesn't know is that the People's Liberation Army has a stake in ALL Chinese companies, even the ones under foreign ownership.
What that means is that not only did those companies do business with Iran in weapons tech transfer, they did it knowing that the government knew too.
don,t you just Love Free Trade
Which is why China is wailing. Slapping these Chinese companies is a direct slap to the "image" of the Chinese Government as a "friend" of free and developed countries.
Until now they've been getting a free pass while they supply Iran, supply North Korea, support fledging communist governments across the Globe, make deals with Russia etc...
If they were a peaceful ally they'd strip NK of nuclear weapons and support regime change in Iran.