>We don't know the details of the strikes, but I hope it doesn't go into a full blown war

Well, if the Chinese are smart, they will capitalize on this opportunity. They can prop up the Iranian regime with intelligence, weapons, and financial support the same way US & EU prop up Ukraine. The purpose would be to bleed US munitions stocks even faster than they already are, as well as increase attritional losses in platforms and personnel. China's stranglehold on rare earths and their export restrictions are making it more difficult for the US to restore its weapons stockpile. I'm sure China can crunch some numbers to identify the point of maximum weakness if the US is forced to sustain an anti-Iran air and naval campaign 30/60/90+ days. Then Xi can try to overlap that window of weakness with one of the two invasion windows against Taiwan (mostly due to weather in the Taiwan Strait). I don't think the PLA is dumb enough to try a full amphibious assault, but they could definitely initiate their blockade then.

I don’t believe China has any intention to support anyone by military means. Best case they will keep on trading and that’s it. Iran is alone. Maybe Turkey makes a crazy move to support seeing it sees itself as next in line if Iran falls. This is the biggest present to European powers, which I think will be hoping that it will keep US busy for rest of Trump’s presidency. They have the Ukraine excuse to distance themselves and let everyone get weaker while they arm themselves up. Internal political tensions in US will also give them leeway to more actively influence American politics and these will be even worse with a long war pitched against a scandal background. Then again, Trump may be a genius, get this done in a couple of months and leave everyone grasping for a new strategy.

It would take weeks for China to shop stuff. (Unless they have done their homework in advance)