This article is also very interesting, if for no other reason than showing that no one knows what is going on.
http://www.washingtonpost.com/wp-dyn/content/article/2006/04/18/AR2006041801630.html
"Mystery Hangs Over Baghdad Battle
Conflicting Accounts Obscure Even Identity of Combatants in 2 Days of Street Fighting
By Nelson Hernandez and Bassam Sebti
Washington Post Foreign Service
Wednesday, April 19, 2006; Page A10
BAGHDAD, April 18 -- As the shooting died down Tuesday afternoon, the tired and frightened residents of Baghdad's Adhamiyah neighborhood packed their cars and prepared to flee. After two days of street fighting that had kept them locked in their houses, they did not want to see what might come next.
The details of the unusual street battle that began Monday remained shrouded by the fog of war. U.S. and Iraqi soldiers thought they were shooting at insurgents who were trying to ambush them. Local men on neighborhood watch in the predominantly Sunni Arab area thought they were shooting at Shiites who were coming to kidnap and kill them. Residents hiding in their homes, simply praying for survival, could only guess who was fighting whom.
"As far as I know, a group of militants went inside and there was fighting with the residents of Adhamiyah, and later on, the police were involved and the MNF-I were involved," said Adnan Ali al-Kadhimi, an adviser to Prime Minister Ibrahim al-Jafari, referring to Multi-National Forces-Iraq, the official name for foreign troops in the U.S.-led military coalition here. "We don't have a clear picture of what's happening there." "