Here's something I've been kicking around as part of a wider TL. The TL itself is somewhat soft and makes use of a number of ASB elements, but I would like to know if there's anything that's horrendously implausible that needs to be revised or redacted. If it would be better suited for chat or the writer's forum, please move it as you see fit.
Forgive me if I seem like I'm rambling.
The actual PoD for the TL is in 1946, when the Soviet Union chooses not to withdraw troops from northern Iran. The reason for this is actually ASB, but I don't feel like that affects the content of this particular thread enough to warrant moving it there. In any case, the Soviets withdraw in the mid-50s.
From there the TL has it's numerous twists and turns, but there are some similarities. One of them is that the Iranian Revolution still occurs in the late 70s and installs a radical anti-American Shiite theocracy led by Ayatollah Khomenei. The Iran-Iraq War takes a similar route to OTL a well, with Iraq (backed by the US and USSR) invading Khuzestan in 1981. The war itself takes some alternate paths here and there, but by 1988, as in OTL, both nations are devastated, but Iraq has the upper hand.
The main divergence occurs in 1988. As in OTL, Saddam Hussein sends a letter to Khomenei threatening a renewed invasion and the use of WMDs against Iranian cities. In OTL, this letter was one of several circumstances that led the Ayatollah's advisors to urge him to seek peace, despite him wishing to continue the war. However, in TTL Khomenei decides to soldier on, for one reason or another (different advisors, different circumstances, etc.)
Early one August morning in 1988, Iraq launches a massive CBW attack against Iranian civilian and military targets across the region. Iraqi MiGs swoop low to drop chemical bombs on Iranian ground targets, while a rain of anthrax and Sarin-tipped SCUDs fall on Iranian cities. Hundreds of thousands of Iranians are killed in the attacks. Among the dead are numerous senior Iranian government and military figures, including the Ayatollah himself. In the ensuing chaos, Iraq is able to crush Iranian forces within their own nation and roll on to take Khuzestan, ending the war with an effective Iraqi victory.
In the ruins of Iran, a power struggle develops between the remnants of the theocracy and allied militias and numerous other factions, including Communists, secular democrats, ethnic seperatists, the odd Shah loyalist, etc. Eventually, tensions boil over into open warfare. I haven't worked out all the particulars, but the war eventually ends in victory for the "Iranian People's Front", something of an alliance between Marxist, Mossadeghist, and even a few Islamist factions supported heavily by a surviving Soviet Union (which continues to occupy Afghanistan well into the 1990s) after many groups still loyal to the regime defect to the IPF, as the regime is unable to pay their salaries and resupply them as foreign support runs dry. The IPF is even able to retake Khuzestan from Saddam (who by this point has largely been abandoned by most foreign backers after his Kurdish genocide goes even further than OTL). Iran is reformed into an "Islamic People's Republic" and becomes a Soviet ally, and a sore sticking point for the US in a continued Cold War.
Some problems I have identified:
1) By 1988, Iranian Communism and other opposition to the theocracy had been pretty well stamped out by Iranian security services. Perhaps an earlier conclusion to the war would allow for more powerful opposition groups to arise, or alternate circumstances mean that the Islamic Republic isn't as competent in suppressing dissent.
2) One of the more prominent Communist groups in Iran, the People's Mojahedin Organization of Iran, had largely discredited itself in the eyes of many Iranians by publicly siding with Iraq and fighting alongside them against the Iranian government. Perhaps they are left out of the IPF, or alternate circumstances lead to them never siding with Iraq and thus never sullying their image.
3) With a longer Soviet occupation of north Iran, would Communism really be popular enough to take power in Iran?
4) Would Iraq have the capability to launch such a crippling chemical strike as the scenario depicts? If so, would the Iranian leadership really be so vunerable?
5) Not really a problem, but what happens to Lebanon and the Lebanese Hezbollah? Would the latter group fight in support for the regime (I assume so, considering the Iranian Hezbollah)? Would the Islamic People's Republic of Iran continue to support Hezbollah after all is said and done against Israel?
6) Many of the Soviet client states in the Middle East (including Syria and Libya) favored the theocracy. My current plan is to initially have them support the Iranian government, but as the war drags on, the tide turns, and the Soviets enforce their will, Syria and Libya eventually shift their support to the IPF. Is that plausible?
One thing is for certain: I need to do a lot more research on the topic before I even begin to write it.