I reckon most analysis of Iraqi politics is off-beam because it analyses the actions of the players in terms of their presumed principals rather than their actual pragmatism. In an earlier post I branded Moqtada al-Sadr a warmonger because he was fairly obviously waging insurrection so as to increase his prominence in the post-war negotiations. Others saw him as a hero because of his brave defiance. This post analyses his latest self-interested manouevrings.
After sacrificing thousands of his followers in Najaf, al-Sadr appeared to have been folded into the civilian horse-trading process, presumably with more influence than he would have had without that sacrifice.
Now he has re-emerged into public, and thousands of his followers have demonstrated against the US occupation. This article from Sify News is the earliest report of it I can find.
Apparently, while they were dressed in uniform they did not carry weapons and were instructed not to retaliate, even if fired upon by the Americans – non-violent resistance in a complete break with their past.
Again, this seems fairly obvious to me to be a gambit to increase Sadr’s influence, and while non-violent, of a piece with the violence. Look at the demands that Sadr is making:

Khazraji read off to the crowd Sadr’s demands of the Iraqi government. They included a quick trial for Saddam; making Thursday the second day off in the week not Saturday, due its association with the Jewish Sabbath; the freeing of all Iraqi detainees; the strengthening of border security; and that the parliament respect the resistance and bring it into the political process.

It is also significant that a number of Sunni clerics urged their followers to join in.
So, the US has made the cost of violent insurrection too high, in his judgement, but he can still muster physical support, so he organises a demonstration. Democracy is the art of building coalitions, so he looks to augment his physical presence through alliance with others.
He wants a quick trial of Saddam (for which read execution), which most of the country would applaud, but which is against the Sunni interest, and he balances this by putting out feelers to them to join with him in his demonstration. At the same time he looks for an anti-Semitic angle – Thursday rather than Saturday holidays – to cast his net more broadly.
The Sunnis will also be interested in the immediate release of all Iraqi prisoners, who must be disproportionately Sunni, as they will with the call to bring the resistance into the government (even though this appears to be happening anyway). I’m not sure who the border security issue is aimed at, but presumably the Sunnis as well, as one border which is insecure is with Iran, a Shi’ite nation. Then again, it might be the Shia, who could be concerned about interference from Syria, or even both Shia and Sunni who might be concerned about the Kurds linking up with their relatives in Turkey with whom they harbour desires of forming an independent Kurdistan. Just like “border security” in Australia, it has some of the timbre of a dog whistle.
We should keep our eyes on Sadr. He has all the makings of another Saddam. Obviously psychopathic and ambitious, he knows how to hide his talons and play the dove, but his Ghandi is about as convincing a peace-maker as Barry Humphries’ Dame Edna is a woman. There’s a lot more turns and twists in this one, but very few gladioli.