This is not merely and purely an issue of religious freedom. It is also the wedge and icon of the decades long power battle between "the generals" and elected governments in Turkey.
In addition to plain fights over power, there is a genuine ideological dimension as well. The secular establishment (including the military) sees attempts to lift the ban as threatening Turkey's "secular principles." In the past,
One cannot look at this just cynically though. The legitimate points of concern from the side of the secular elite is the express fear that lifting the headscarf ban could put pressure on women to wear ever more conservative attire, and open new avenues for the government to impose strict versions of Sharia law on public and private life. These are highly sensitive issues that often dominate the national agenda.
Still on principle alone it is necessary to side with Erdogan who insists that lifting the ban is nothing more than a question of individual liberty.
This claim to simplicity is not true in the context of Turkish power politics, and highly charged questions involving culture, religion, and even Turkey's own directions on policy and international relations. Still, even in such complex and complicated issues of politics and policy, it remains necessary to uphold the ideal of personal liberty, especially in the arena of religious freedom. We cannot be comfortable when governments impose on the free expression of personal faith. We do not want Turkish Muslims barred from their sacred obligations any more than we would hope to see such constraints and impositions on Muslims citizens in Holland, Germany, or France.