Russia isn't moving for obvious reasons (I don't think IRGC planners even expected them to move, Putin has made it clear a 100 times he is out of anything involving Israel). But that said Putin arguably did his job already by destroying Patriot stocks and thus putting US on a timeline in terms of protection.
With China the issue is different: They have a completely different military ecosystem so it's not like they can send them their own stuff. We already saw in Ukraine that running 2 types of equipment along each other is a pain in the ass and strains logistics. China is likely aiding them with satellite imagery instead.
I think China will sit this one out. There's nothing to gain for them with direct involvement.
Any assistance to Iran (like satellite imagery) will have limited effect, and the Chinese know it. In my opinion, there's no way the Islamic Republic survives this. For any rational international actor, there's no sense in becoming involved in a lost fight.
> In my opinion, there's no way the Islamic Republic survives this.
But what if the Islamic Republic isn't a material thing, it isn't a government apparatus, it is actually the ideas and culture of a population under siege? 50-60 million Persians, and another 30-40 million muslims of other ethnicities. They have been embargoed for decades, the message that the US and Israel are evil has seeped into every corner of society there. It will not be so simple to erase that programming and you can expect a large portion of the population to resist to the bitter end. It's been over 20 years of planning to bring the USA to this point, 20 years because it was never a sure bet, and even today it's still not clear who wins. No, I think 4 days in it's too early to call winners and losers.
With China the issue is different: They have a completely different military ecosystem so it's not like they can send them their own stuff. We already saw in Ukraine that running 2 types of equipment along each other is a pain in the ass and strains logistics. China is likely aiding them with satellite imagery instead.