Turkey’s two-faced ‘sultan’ is no friend of the west. It’s time to play hardball

President Erdoan's increasingly hostile stance towards Nato and democratic principles can no longer go unpunished

That Turkey is a vital strategic ally" of the west is the sort of truism on which people such as Joe Biden and Jens Stoltenberg, Nato's secretary general, are raised. Yet what if the old saw no longer holds true? What if Turkey's leader, exploiting this notion, betrays western interests in a pretence of partnership? Should not that leader be treated as a liability, a threat - even ostracised as an enemy?

Geography doesn't change. Turkey wields significant influence at the crossroads of Europe, Asia and the Middle East. Yet the increasingly aggressive, authoritarian and schismatic policies pursued at home and abroad over two decades by its choleric sultan-president have upended long-cherished assumptions. Turkey's reliability and usefulness as a trusted western ally is almost at an end.

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