Sadr and his followers served their purpose for the Shia and made sure the US knows that first and foremost, the majority Shia in Iraq have to be reapected or they will pick up guns and fight. Once US showed appropriate respect to the Shia majority, there was no more need to fight. The Shia will be the dominant political and social power in Iraq.
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The most important thing is for us to find Osama bin Laden. It is our number one priority and we will not rest until we find him.
-- President George W. Bush, September 13, 2001.
I don't know where he [Osama] is and I really don't care. It's not that important. It's not our priority.
-- President George W. Bush, May 13, 2002.
http://www.slonet.org/~rloomis/quote.html