Tom Madden in First Things (hat tip: Matt Phillips):

Hagia Sophia’s transformation into a museum in the 1930s was in large part due to an American socialite and fundraiser, Thomas Whittemore. With support from Mildred and Robert Woods Bliss of Dumbarton Oaks in Washington, D.C., Whittemore obtained permission from the Turkish government to uncover and restore the medieval mosaics of Hagia Sophia. Beautiful depictions of Christ, the Virgin, saints, and emperors arose gloriously from their centuries-old plaster prisons. Armed with cameras and a good head for publicity, Whittemore brought the sublime images of forgotten Constantinople to an astonished world. 

President Mustafa Kemal Atatürk, the father of modern Turkey, took a keen interest in these discoveries. Atatürk was determined to modernize Turkey, bringing it out of its medieval past. That meant, among other things, distancing the new Republic of Turkey from the old Ottoman Empire. He had already moved the capital from imperial Constantinople, and even changed the name of the city to Istanbul. He had also opened Topkapi Palace to tourists. Transforming the sultans’ old mosque into a museum fit perfectly into that program. In 1934 the Turkish Council of Ministers declared Hagia Sophia to be no longer a mosque, but “a unique architectural monument of art.” And so it remained, until last week.

Some have suggested that the decision to make Hagia Sophia a mosque fits with the statue toppling and cancel culture in the U.S. and Europe. But it is really just a political move. As his popularity among moderates and progressives has faltered, President Erdoğan has become increasingly reliant on rural Islamic conservatives to keep him in power. They have always cherished hopes of reverting Hagia Sophia to a mosque, as they believe Atatürk’s reforms betrayed Islam in a bid for Western acceptance. In the most recent elections, Erdoğan lost the majority in Istanbul. So this decision, loved in the countryside but hated by progressives in the big city, both rewards the president’s supporters and punishes his enemies.

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Like all buildings of such age, the history of Hagia Sophia is complicated. For nine centuries it was a church, for nearly five centuries a mosque, and for almost one century a museum. It has been the site of unparalleled beauty and unspeakable horrors. The history of the West is bound up in that remarkable building. It should not be reduced to a pawn in a political campaign. Hagia Sophia should no more be a mosque than the Parthenon should be restored to the worship of Athena. These are shared historical monuments, where people of diverse backgrounds can see our common human experience. The world has plenty of churches and mosques. Let Hagia Sophia be Hagia Sophia.