Wouldn't they want to weaken the Iraqi regime more than they would want to avoid alienating the Turks? Especially if they had a large Kurdish refugee problem (similar to the Palestinians), wouldn't they care more about appeasing their domestic Kurdish population and creating instability in Iraq then their relationship with Turkey? Another point is that by becoming the Kurds' patron, the Iranians gain a level of power of the Turks, as they can back Kurdish uprisings or block them through their control over the Kurdish nationalists' arms supply.
The Kurds are not someone you just control. The Kurds have oil to sell on the world market, they have the Soviets to get/buy weapons from and they have Syria to act as their window to the outside world. Hell, Southern Kurdistan will probably be even more pro-Soviet than Baathist Iraq. They're not in Iran's pocket and they'd be unreliable even if they were. The aspirations of Iranian Kurds are more likely to be fueled than appeased - after all, an independent Iraqi Kurdistan doesn't offer them anything besides an example.
Weakening Iraq was achieved by either keeping the regime and the Kurds at war with each other (and backing the weaker side) or being able to threaten it with a Kurdish uprising if it didn't behave. The Kurds were not Iran's friends, just a lesser enemy turned ally of convenience; you don't want to do them any great favors and you don't want them and the greater enemy to reach any final peace settlement and then potentially turn against you, both of them.
And the alliance with Turkey was a big fucking deal.
While they want the Sinai back, Sadat may feel that the best way to do that is through hostile action once again as opposed to negotiation. The USA, if it continues to support Iran through the whole debacle of a war, will have showed Egypt that it isn't serious about supporting it. That might have pushed Sadat back towards his routes in Nasserism. It might even cause a uprising or coup if he didn't push back.
US support for Iran would mean nothing to Sadat. Saddam was not his friend, the Shah was not his enemy and his OTL actions show that he did not believe in some international Arab cause that had anything to do with getting the Sinai back. The US actions that interested him first and foremost concerned Israel and the occupied territory. I don't think even Nasser would have thrown away that opportunity for Iraq's sake, all rhetoric to the contrary. If anything, the US bailing out on a major ally would create doubts as to the worth of improving relations with Washington.
Wouldn't Arab states still fear a non-Arab, Shi'a interloper in their territory, especially one that would create the precedent that an oppressed minority can free itself with foreign help? Why couldn't the Palestinians in Jordan do it? Or the Christians in Syria? Or the Shiites in the Gulf? Or the Copts in Egypt?
They wouldn't see it in terms of Arab vs non-Arab. The conservative regimes never believed in Arab solidarity, only referred to it on occasion and for ulterior motives. The radical regimes believed in it to some degree, but that didn't prevent Syria and Libya from backing Iran in the OTL war. As for the Shah, foreign Shiites were not his main concern; he certainly didn't let them prevent cordial relations between his monarchy and those of Saudi Arabia and (pre-1958) Iraq. If he initiated the war, or if he intends to end it with his troops in Baghdad, he did it only to eliminate a powerful rival. As I said in my first post in this thread, Syria and the Gulf monarchies would be on the fence in such a scenario, not because they saw the region through this lens you're pushing on them but because Iran would then transform from an ally threatened by a rival into an ambitious power seeking to eliminate that rival. Under the alternate scenario, their support for Iran would be unquestioned.
You think they would attack Iran? Would they actually send tanks over the border? Wouldn't they hold off on such a drastic step because it would risk bringing the Americans into the war directly? I feel like they might do what the Americans did in the Yom Kippur War, and fly repainted Soviet planes into Iraq pretending they are Iraqi and Syrian planes that were "training" in the USSR. The ruse might work, and even if it didn't, it would create plausible deniability for the American, allowing them to stay out of a potential nuclear conflict. Both Carter and Ford, whoever is President at this point, won't be willing to support Iran militarily unless Soviet tanks cross the border.
None of the superpowers wanted WWIII, but both were willing to risk it to protect major allies. I think I expressed myself wrongly - war with Iran would not be the Soviet's first option for saving the Baathist regime, but it would be an option. If massive deliveries of weaponry and munitions and the secret dispatch of Soviet forces doesn't do the trick, an ultimatum will be delivered to Iran, and it won't be a bluff. Backing down risks compromising Soviet credibility in the 3rd World just as they were making their greatest advances there.
Agreed. Likely, the war would be short. bloody, and would end with a different Iraqi government (likely still Ba'athist, maybe with more Communist influence) and an independent Kurdistan.
I already explained why I don't agree with that.