Iran is surrounded by Muslim nations and cannot easily send an army into a non-Muslim nation to fight a war. Their armored divisions are not about to roll into Israel.
They are a terrorist nation, but the world lives in that shadow no matter what.
Iran has no real friends, no real alliances. If someone were to stage a major attack against Iran, removing their nuclear capability, what happens next? What are the repercussions? Frankly, I'm not sure I see any. Of course, we live in a world where "you don't do that". But we clearly live in a world where Hamas "does that". I think it's time some nation just takes out Iran.
Also, Iran is not an Arabic country.