Drastic changes to a constitutional system are not to be undertaken lightly. Many systems. like the US, make amendments extremely difficult. Supermajorities are often necessary. Yet, despite suppressing the media and silencing the opposition, Recep Tayyicp Erdoğan's referendum squeaked through with a 51-49 "Yes" vote, losing in all the country's major cities hardly a resounding endorsement. Erdoğan's victory is being disputed over a decision to count ballots not properly stamped.
Some intelligent commentary: Yavuz Baydar at The Guardian,
"Erdoğan’s referendum victory spells the end of Turkey as we know it." On a similar theme, Steven A. Cook at Foreign Policy laments "RIP Turkey 1921-2017." Cook acknowledges that the Turkish Republic was far from a perfect democracy, but I feel he overstates the break between the Ottomans and the Republic (the Ottomans wrote constitutions in 1876 and 1909, and Westernization began with the Tanzimat). And while he acknowledges flaws in the Republic, I feel he understates the authoritarianism of the Kemalist era, not to mention the interludes of military rule.
The Erdoğan/AKP phenomenon is, as both authors recognize, a reaction to the excessive secularism of the Kemalist era, and part of a (global?) reaction of conservative, religious, rural and small town voters resentful of the urban secular elites who they feel have looked down on them for years. But their revenge may come at the price of Erdoğan's authoritarian ambitions.