Since the insurgency began after Baghdad fell in spring 2003, 19,429 militants have been killed in clashes with coalition forces, statistics show. The numbers do not include enemy killed during the invasion.
The statistics, provided at USA TODAY's request, were retrieved from a coalition database that tracks "significant acts." Militants are identified in the database because they are linked to "hostile action," said Capt. Michael Greenberger, a Freedom of Information Act officer in Baghdad. There is no way to independently verify the data.
As of this morning, Icasualties.org is reporting a total of 3358 Coalition (non-Iraqi governmental) forces combat fatalities [data derived from here, accessed 9/27/07), and 4,101 total uniformed deaths. So Coalition (non IG) forces are inflicting a 5:1 to 6:1 kill ratio against all insurgent and militant groups over the past 4 years if we trust the US government data. Assuming we do trust the data to be reasonably accurate +/- e, and remembering that the early learning of the Mahdi Army in 2004 in Najaf contributed to a significant portion of the total militant body count, the Coalition forces are barely treading water with superior air power, artillery, armor, and medical facilities. Throw in the 7,500 or so Iraqi government security force fatalities, the insurgencies are trading 2:1.
This has been a consistent ratio with some bouncing around and outlier months such as August 2004 when the Mahdi Army thought it would be a good idea for an ill trained light infantry urban guerrilla and mafia force to fight a pitched, set piece battle against two US heavy brigades. It is a fatality rate that the civilian supporters of the multiple insurgencies can absorb and easily replace from normal birthrate additions. This would have been true three years ago when the proportion of Sunni Arabs who believed it was justified to shoot at US forces was a fraction of today's near unamimous opinion within the Sunni Arab community, and it is more pronounced within certain Shi'ite Arab communities.