You are wrong. Iran is building missiles that can reach Europe. When it gets nukes it will threaten Europe, Israel and Saudi Arabia with them. We have allies and interests in Europe and the Middle East and Iran will soon be in a position to mess around with them. Russia, China and Iran will carve up the Middle East oil resources and nations. Short of this they will tell Arab oil nation how much oil to sell and to whom and to pay $10/barrel tax to Iran
As for the Saudis, they're much bigger sponsor of Islamist jihad than Iran will ever be.