Which Toby Keith song are you referencing?
And here are the major things to consider:
1. Terrorist insurgents. However, we are already having to deal with those. You seem to think more will come into play, I find that hard to believe, but, yes, that is a possibility.
2. Russia. Russia is a major factor in this whole operation given their status with Iran as an ally.
3. Other countries in the region. Other countries are not happy with Iran either and would likely join the US in an operation against the country after we make the initial move.
Those are the major factors at play right now.
I’ve already mentioned number two. I have a hard time believing any country in the world is itching for number three.
As for number one, I don’t know why you would find that hard to believe given how Arabs tend to place tribal loyalty over patriotic loyalty.