The U.S. invasion of 2003 ousted Hussein and elevated Shiites to positions of power but the war also fanned longtime tensions between Sunnis and Shiites. Many feared hostilities would explode into protracted civil war, though the violence had ebbed by the time the last U.S. soldiers exited Iraq last year.
However, militant Sunnis have not stopped attacking Shiite pilgrims, and the scale of attacks in has June sparked fears of renewed violence on levels of the past.
MORE: http://www.cnn.com/2012/06/25/world/meast/iraq-violence/index.html?hpt=imi_c2
