>>which the latter will easily win anyway

There would be literally nothing easy about fighting Iran, unless your idea of fighting is just to glass the entire country. Because any kind of conventional warfare with Iran would make Iraq and Afganistan look like kindergarden in comparison. And that's not to say that Iran is some kind of superpower - it's absolutely not. Just that the terrain is extremely difficult, the army is actually decently equipped and trained, and it's a huge and very populous country.