The USA attacked Najaf.
If the US military truly attacked Najaf, there wouldn't be a city left. Now, with that in mind, a more accurate statement would be, "a small expeditionary force was sent in to Najaf due to the pressing need to kill the terrorists there."
As for your karma theory, um... no. Go learn some statistical analysis. Florida has been overdue in terms of hurricanes for a long time now. The Carribean islands got more storms than Florida did, but they didn't have troops in Najaf. There was a large storm in China, and it caused mudslides, killing a few hundred people, but China didn't have troops in Najaf.
I used to think Blue's News posters were smarter than Shack News posters. Lately, I'm not so sure.