In Through the unknown, remembered gate, Wretchard cites a Washington Post story about casualties in Iraq:
Between March 21, 2003, when the first military death was recorded in Iraq, and March 31, 2006, there were 2,321 deaths among American troops in Iraq. Seventy-nine percent were a result of action by hostile forces. Troops spent a total of 592,002 ‘person-years’ in Iraq during this period. The ratio of deaths to person-years, .00392, or 3.92 deaths per 1,000 person-years, is the death rate of military personnel in Iraq.How does this rate compare with that in other groups? One meaningful comparison is to the civilian population of the United States. That rate was 8.42 per 1,000 in 2003, more than twice that for military personnel in Iraq. The comparison is imperfect, of course, because a much higher fraction of the American population is elderly and subject to higher death rates from degenerative diseases. The death rate for U.S. men ages 18 to 39 in 2003 was 1.53 per 1,000 — 39 percent of that of troops in Iraq. But one can also find something equivalent to combat conditions on home soil. The death rate for African American men ages 20 to 34 in Philadelphia was 4.37 per 1,000 in 2002, 11 percent higher than among troops in Iraq. Slightly more than half the Philadelphia deaths were homicides.
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Marines are paying the highest toll in Iraq. Their death rate is more than double that of the Army, 10 times higher than that of the Navy and 20 times higher than for the Air Force. In fact, those in the Navy and Air Force have substantially lower death rates than civilian men ages 20 to 34. … Lieutenants have the highest mortality of any rank in the Army, 19 percent higher than all Army troops combined. Marine Corps lieutenants have 11 percent higher mortality than all Marines. But the single highest-mortality group in any service consists of lance corporals in the Marines, whose death risk is 3.3 times that of all troops in Iraq.