War in Iraq is going to get more serious than anyone had anticipated. Latest attack on British show that the resistance movement has broadened its activities towards south where majority of population is made of Shiites (who are, unlike Sunnis in Central Iraq, hardly nostalgic towards Saddam). Furthermore, British have more experience with counter-insurgency and winning "hearts of minds", unlike their trigger-happy American allies. However, it is too soon to judge whether this killing is isolated incident or sign of things to come.
In the same time, poll shows that more and more Americans are getting uncomfortable with the level of US casualties in Iraq.