Iraq has launched its largest security operation to date to free not only Tikrit but central Salahaddin province as well. Much has been made of the presence of militias and popular mobilization brigades that might be as much as two-thirds of the total force. Iran and Lebanese Hezbollah are playing a big role as well providing not only advisers but air cover and artillery as well. With the United States opting out of participating in this offensive due to Iranís large presence, it could be a turning point where Tehran solidifies its place as Baghdadís main ally in the war against the Islamic State (IS).