The Hagia Sophia is one of the most beautiful and well-known buildings in the world — and Islamists have detested that fact for years. After all, it is a Christian church, and therefore a Christian symbol.
That’s why the Ottoman Turks wasted little time transforming the church into a mosque when they invaded and conquered Constantinople (Istanbul) centuries ago. Christian symbols and works of art were destroyed or covered, and a dominating tower was built from which the Islamic call to prayer could be sung.
The Ottomans did that because they wanted to show Christians that, from then onwards, Islam was in power. Christianity would be subjugated.
That changed in the 20th century, when the Ottoman Empire fell and was succeeded by the secular Turkish Republic. The Hagia Sophia was declared a neutral place for Christians and Muslims (and for people of all other religions). The church/mosque was made into a museum where everybody was welcome.
Just about everybody was happy with that situation — except for the remaining Islamists. Thankfully, fundamentalist Muslims were marginalized in the Turkish Republic.
Sadly, that has all changed under the rule of Recep Tayyip Erdogan, Turkey’s current president.
Erdogan is an Islamist who believes that Turkey can only restore its old glory (note: the glory days of the Ottomans) by becoming a truly Islamist nation. That’s why nobody was surprised — shocked, yes, but not surprised — when the government announced earlier this year that the Muslim call to prayer would be sung twice a day in the Hagia Sophia from then on.