A good thing about the Iraq war??

I have been to Iraq. I was deployed there in 2004. While there I couldn't find any reason why I was there. I would look into the faces of the inhabitants of Baghdad and all I found was pure hate and mild insanity. I lost three soldiers in Iraq. All three where great men and all where not old enough to drink. I have struggled to find a purpose for thier loss. I know they gave thier lives for me, but what was the overall point to it? Can anyone give me one good thing about us bieng in Iraq? If I can find some good then maybe I could lay aside the guilt I have for lossing my men over there.