Iran and Iraq were at war from 1980 until 1988. Not much room to move in unless the Saudis decide to back the expansionist war of Iraq. Not sure if the secularism of Iraq would have been a bit issue at the time. This happen before the seizure of the Kaaba and the Saudis deciding that people who shoot up their holy places should be appeased by all means? Anyways, the Saudis might not like the idea of Iraq getting too much dominance in the area. Gotta find a way form them and the Gulf States to go to war with Iran. Maybe some massacres of Arabs? There are quite a few of them around the northern shores of the Straits of Hormuz. I doubt there would be massacres on the part of the Iranians, though. The ethnic cleansing of people who had been loyal to centuries (besides, their country was made up of more than just Persians) never really seemed to be Iran's style.