> AFAIK there is no exemption that says it is OK to commit war crimes if the other side does.

Of course not, but I still think the expectation that someone doesn't commit war crimes against you disappears relatively quickly when you're openly and proudly admitting you'll open to violating the rules of war and saying international humanitarian law doesn't matter.

That may be so, but remember that Ukraine is fighting for its very survival, and Iran may be as well.