Dave, good analysis, and take an extra sip of the Sherry - I'll join you.
You're absolutely correct in stating that none of the countries involved have acted with entirely Simon-pure motives. Some are more opaque than others, but it becomes difficult to trust ANY of them.
On the 200+ UN resolutions, please remember that the UN is basically a farce - everyone ignores UN resolutions because they simply have no teeth. Additionally, the UN resolutions are FAR from impartial. Outer Camelstan can introduce a resolution which is total nonsense, but since they are a member of Bloc X, all the other countries in Bloc X will vote for this, even if it resolves that the earth is flat. Countries seem to feel the same way about UN resolutions as Chavs feel about ASBOs - high score is a mark of pride (whether or not it should be is another matter).
The only real problem I see with your analysis is that it assumes the Mullahs are rational actors. While they are interested in self-preservation, they also subscribe to various apocalyptic messianic visions involving the immanent return of some Mullah or other from the 8th century, and they figure they might as well give him a rousing welcome by eliminating various (perceived) enemies of Allah as a token of their piety.
They are also using a very old propaganda trick to help themselves stay in power. That trick is to create an external enemy (real or imagined, doesn't matter) to rally the populace around them, and to distract the populace from the very real and ongoing internal problems of the country and the regime.
Israel doesn't plan to invade Iran and doesn't even want to - and couldn't anyway - yet the Mullahs loudly and constantly insist that Israel is a mortal threat and should be "wiped off the map". That's pretty paranoid, and paranoia plus nuclear weapons is a bad combination. It is even worse when one side feels they have nothing to lose because the world is about to end anyway.
As to the Cousins invading Iraq, I suspect we won't know the real reasons for this for probably 50 years. It may very well be that Dubya just got confused and invaded Iraq instead of Iran because heck, there's only two letters difference anyway, so where's the problem?
If push comes to shove and the US and Iran do decide to duke it out, the result will be messy, violent and brief. Remember that Iran and Iraq fought for eight years and it was a draw (both sides lost), while the US dismantled the Iraqi military in a few weeks - and has been playing whack-a-mole-since. This is a very dangerous situation, because if Iran does figure out how to build a bomb, their biggest problem will be deciding where to use it - and Israel is a prime candidate. That won't affect the result of the war, but it will kill a lot of Israelis who were otherwise uninvolved.
International politics is a VERY high stakes game - when you add religious fanaticism and nuclear weapons, everyone will lose.
Maybe I'll have some more Sherry . . .