Wait, Assad hated Sadat that much? Fair enough. So there would definitely be civilian casualties, war crimes, and such...because Assad had a giant ego and little tact. Fantastic.Well, these two points are not really correct, at all.
Assad more or less hated Sadat, partly because Sadat was actually competent and partly because Sadat stood between Assad and what he thought would be leadership of the entire Arab World. The only way Sadat could stop Syrian troops from excesses is if he had Egyptian forces attack them directly (good luck on that one, just keeping their conscripts reined in was going to be a full time job for the Egyptians).
I know that Syria is basically Russia's warm-water port, but I strongly doubt that Moscow would launch the nukes if not directly attacked themselves, precisely because they knew what the stakes were.Nixon reacted when the October War started to turn against Israel and IDF started to, quite obviously, begin prepping their Nuclear Deterrent (which was exactly WHY the Israelis made the preparation so bloody obvious). Israeli use of Special Weapons against Syria, a major Soviet Ally, was one of those nightmare scenarios that tended to escalate to a full exchange in the blink of an eye. A full nuclear exchange qualifies as a bad thing. Nixon also went full Cold Warrior once the Soviets started to talk about intervention, hence his taking SAC to DEFCON Three to remind Moscow just what the stakes were. Nixon didn't support the Israelis due to political calculations (or looking to capture the "Jewish vote") by then his only political calculations related to staying in office and out of the slammer), he supported them because failing to do so could have resulted in Armageddon.
I dunno. I know I'm an optimist about human nature to the point of being misguided, but I just can't imagine Israel or the USSR (even Leonid Brezhnev's USSR) stabbing themselves in the heart to soak their enemies with their blood like that.