1) ISCI/SCIRI began life as a creation of the Iranian Revolutionary Guards. It was originally a breakoff faction of al-Dawa which split mainly because its members chose to follow Ayatollah Khomeini's doctrine of vilayet-i-fiqh, or clerical rule. It may have achieved some independent political life since 2003, but its IRGC ties are strong and well-documented. Its political position regarding Iraqi federalism (advocating for a strong southern federal region with near-independent powers) is in line with Iranian interests.

3) Who knows proper casualty figures - I doubt anyone does. What matters is that the ISF was unable to seize or maintain control over any Mahdi Army strongholds in Basra until Sadr told the militia to stand down, while Sadr's forces were able to launch attacks throughout the south and put the ISF on the run in numerous locations including in Nasiriyah. I saw TV footage of Mahdi Army militia strolling about in broad daylight as late as yesterday, as well as several Mahdi Army fighters driving captured ISF hummvees. That Maliki extended his "deadline", took the deal, as well as claiming all along that he never targeted the Sadr Current specifically, shows that the ISF did not exactly sweep all before it.