Extending data reported by Hafez in 2007, we compiled a database of 1,779 suicide bombers who attempted or completed attacks in Iraq from 2003 through 2010. From 2003 through 2006, monthly totals of suicide bombers show a pattern different from the pattern of non-suicide attacks by insurgents, but from 2007 through 2010 the two patterns were similar. This biphasic pattern tests the common assumption that suicide attacks require separate analysis: it appears that suicide attacks sometimes vary along with the general volume of insurgent violence. We also show that only 13 percent of suicide bombers targeted coalition forces and international civilians, primarily during the early years of the conflict, whereas 83 percent of suicide bombers...