Eric Posner from U. Chicago estimates the war saved about 300,000 Iraqis (extrapolating from data under the sanctions regime vs. deaths during the war). He even analyzes the effect on children.
The sanctions regime, which began in 1990, destroyed Iraq’s economy (reducing GDP by as much as three quarters) and impoverished millions of Iraqis. Particular attention was given at the time to its effect on children. The contemporary critics of the sanctions pointed out that before the sanctions began, the child mortality rate was about 50 per 1000; during the sanctions, on one accounting the rate soared to about 128 per 1000 (click on "basic indicators" here). More conservative estimates were in the range of a doubling of child mortality. Using the more conservative estimate, at one million births per year, this works out to an annual difference of 50,000 children surviving to the age of 5 (for various qualifications, see here). Today, the child mortality rate is below the pre-sanctions figure, and so every year in excess of 50,000 more Iraqi children survive than during the sanctions. The data are hotly contested but the trends are unmistakable and will continue to strengthen if security improves. Meanwhile, violent deaths of civilians, while still far too high, are declining; a very cautious estimate of 500-800 per month, based on the most recent reports on the Iraq Body Count website, is much lower than the avoided deaths of children compared to the sanctions regime. A conservative estimate is that more than 40,000 Iraqis survive per year today than during the sanctions regime, and probably most of them children. The tight correlation between GDP and child mortality across countries bolsters this conclusion.Curtsy: Weekly Standard