"Any spot used by the enemy for hostile operations against Iran will be subjected to retaliatory aggression by our armed forces," Hossein Salami, deputy head of the elite Revolutionary Guards, told the semi-official Fars news agency Sunday.
This threat is obviously directed at countries like Saudi Arabia, the United Arab Emirates, Kuwait, Oman, Qatar, and Bahrain, which are close by. I assume it also extends to Afghanistan where we have a lot of aerial assets close by.
But it could also apply to countries that simply let (or don't stop) planes from crossing their air space to attack Iran. So Turkey and especially Iraq could be the target of the threat.
But aside from the problem of making partial enemies into full enemies by directly attacking somebody who provide perhaps minimal support to an American or Israeli attack, the threat could harm Iran.
The threat of Iranian retaliation might deter countries from helping us attack Iran's nuclear facilities.
Or, if the countries believe Iranian possession of nuclear weapons is unacceptable, it might make them urge an even stronger strike that targets the Iranian regime itself that might order retaliation rather than just the weapons.
When you strike a king, kill him, and all that.