I just don’t see it. Russia dumping weapons at discount rates (well, free, plus some wheat shipments to make sure there’s some soldiers with enough energy to actually unload the ships) on North Korea would enrage China to no end.
If Russia actually wanted to weaken the US, more arms shipments to Iran and Syria would certainly fit the bill. Or hell, just make a major endowment to the Southern Poverty Law Center; feed the US’s 5th column and they’d happily make US cities burn throughout the summer.
Huh. Reminds me, wonder why there’s never a report on the environmental impact of rioting?
And China has their own ambitions and those ambitions are not completely compatible with our ambitions.
So America needs to establish who exactly her allies are and aren't because it isn't 100% clear with regard to the superpowers. The post WW2 paradigm is shifting. The global situation has changed and it is not as favorable to the USA as it was a few decades ago.
The best thing we could do would be to kick the shit out of NK and Iran at the same time with no help from anyone. That would be glorious. That would reestablish our supremacy in the world but the aforementioned players would move heaven and earth to see to it that that doesn't happen which makes that kind of unilateral action exceptionally dangerous.
If we attack either of these countries, we should fully expect a WW3 level event IMO and we should approach it with that in mind.