The problem for Russia is that such an attack would bring in all of NATO which they likely can't defend against. And either way would result in massive damage to nearly everything in Russia.
OTOH, Israel can attack Iran and as shown in the past[1], Iran will roll over and only send a weak-ass slow drone attack as a response.
[1] https://en.wikipedia.org/wiki/October_2024_Iranian_strikes_o...
> Russia would be bombing all the supply lines of weapons flowing into Ukraine if the consequences weren't so high. There's certainly no law that is preventing them from doing so, only the consequences of their actions.
Remember when Russia invaded Ukraine and people in the comments threw their hands up and said the strong take what they can? No, me neither.
https://en.wikipedia.org/wiki/2014_Vrb%C4%9Btice_ammunition_... is one such example.