Is this the end of Turkey's flirtation with Europe?

European relations with Turkey, a NATO ally, have been rattled for years by issues from the flood of migrants into Europe via Turkey to Turkish President Recep Tayyip Erdoğan’s authoritarian slide.

But Turkey’s current shrill dispute with the Netherlands, replete with accusations of Dutch "Nazism" and Turkish "hysteria," threatens to tear open the divides between Turkey and the European Union. Never in recent memory has the rhetoric signaled so sharply that both sides are turning away from each other, and rethinking the contours of their prickly but essential ties.

Europe counts on Turkey as an ally in a hostile neighborhood and beyond. For years, the starting point of any cooperation was Turkey’s bid to join the EU, whether that bid was realistic or not. Success now looks further out of reach, especially if Erdoğan wins a referendum next month to create an all-powerful executive presidency, his long-stated aspiration.

“The big question is, what is the new basis for cooperation?” says Raphael Bossong, a research associate at the German Institute for International and Security Affairs in Berlin. 

Doubts in Europe are mirrored by doubts in Turkey, where officials of the ruling Justice and Development Party (AKP) complain that the EU is in breach of the deal to stem the exodus of immigrants from Syria and elsewhere – which Turkey has largely achieved – because it is not fulfilling promises of visa-free travel for Turks in Europe.

'More than rhetoric'

The latest crisis erupted over AKP ministers’ bids to address Turkish citizens in the Netherlands over the weekend to urge them to vote “yes” in the referendum on constitutional changes. Such campaigning is blocked in Germany and elsewhere. 

The Dutch, citing security concerns on the eve of its own vote on Wednesday, physically blocked two Turkish ministers from speaking. Protests by Turks in Rotterdam were put down by riot police with dogs, which both inflamed nationalist media in Turkey and yielded praise from Geert Wilders, the Dutch anti-Islam, anti-immigrant candidate who is set to gain support in the election.

Erdoğan has railed against the continent’s slide into “fascism,” while encouraging Muslims to vote against standing governments in the Netherlands today, and later in Germany.

Dutch Prime Minister Mark Rutte had harsh words for Erdoğan, while the Swiss tabloid newspaper Blick published a headline in Turkish, calling on Swiss Turks to "vote NO to Erdoğan's dictatorship” in the April 16 referendum.

The firestorm indicates that Turkey under the AKP is increasingly resolute in its turn away from the West, and toward eastern friends such as Russia.

“That is something relatively new. It’s more than rhetoric,” says Cengiz Aktar, an expert on Turkey-EU ties at the Istanbul Policy Center of Sabanci University.

Turkey “has been Westernizing the last 200 years, and in the last few years it is clearly de-Westernizing, this is the main trend,” says Mr. Aktar. “It is really getting out of Europe by all means, values, standards, principles, on everything,” he says. “And [Turkey] is Middle-Easternizing, clearly, and Islamizing.”

He notes that Turkey’s EU membership bid is a “closed file” for Europe, and that the working agendas of neither the past, present, nor next European presidencies include Turkey. Economic benefits of close ties, including transparency and the transfer of know-how, are likely to fade over time as uncertainties grow.

“For Turkey, it’s definitely a losing pattern. The country will suffer out of it,” says Aktar.

Amid the crisis, Turkish officials suggest instead that the "biggest damage" will be to Europe, not Turkey. "Nobody will benefit from racism and fascism. They are the signals of a great destruction in Europe," said Numan Kutulmuş, the deputy prime minister.

Hard situation for mainstream Europe

If the anti-Western rhetoric plays well among Erdoğan’s base in Turkey, it also gives an edge to populists like Mr. Wilders or French National Front leader Marine Le Pen.

“They are all trying to exploit the Erdoğan narrative to their advantage, saying ‘we told you all the time that Turkey has nothing to do with Europe,’” says Marc Pierini, the EU's former envoy to Turkey. It ultimately could even whip up more anti-Muslim rhetoric.

For Wilders specifically, who left the Liberal party to form his own in 2006 precisely in protest of the party’s position on EU accession talks with Turkey, this is the “jackpot,” says Mr. Pierini, a visiting scholar at Carnegie Europe.

The spat could be a challenge for the mainstream in Europe, where nations have taken different tacks to Turkey’s electioneering on their home soil. The Netherlands outright banned the planned visits by Turkish officials; Germany didn’t officially do so at the federal level but allowed local officials to ban them with arguments that public safety couldn’t be guaranteed. Denmark has asked officials to delay a visit.

In France, where a high-stakes election is a month away, the government of Socialist President François Hollande allowed a Turkish rally to take place Sunday. That decision was widely criticized by all top contenders in the presidential race. The frontrunner, Emmanuel Macron, condemned what he called Turkish provocations and urged Europe to a “united response.”

Indeed, EU disunity is a source of the sensitivity to the politics of Turkey in the first place. As various countries in the EU refused to agree to quotas to share the burden of record refugee flows in 2015, Germany looked to Turkey to stem the influx to Europe.

That deal, which includes sending migrants who make it to Europe back to Turkey, drew criticism over fears that the human rights of those migrants wouldn’t be guaranteed. The picture is complicated by Erdoğan’s authoritarian moves at home.

Fabrizio Tassinari, head of foreign policy at the Danish Institute for International Studies in Copenhagen and a visiting professor at Humboldt University in Berlin, says the pact shows a Europe that doesn’t adhere to its own ideals. “On questions of credibility, on reputation, Europe stands to lose much more than Turkey,” he says. “We deliberately looked the other way in order to close this deal.”

No-return territory?

Turkish officials say the EU has been “stalling” them on the promise of visa-free travel, and so Turkey has no reason to continue stopping the flow of migrants. Foreign Minister Mevlüt Çavuşoğlu asserted Tuesday that the EU was on the “verge of falling apart.”

With banner headlines such as, “The Netherlands Surrenders to Fascism,” pro-AKP newspapers asked the question, “Why did West lose Turkey’s friendship?”

“Especially since 2013, Turkey’s national interests have been at odds with Western goals,” wrote columnist Yahya Bostan in the pro-AKP Daily Sabah. He asserted that the US and EU “turned a blind eye” to a July coup attempt last year, and “left a NATO ally alone in the whirlpool called Syria.”

“You lost Turkey because you have no moral or political appeal left whatsoever,” Mr. Bostan concluded.

Still, the EU is Turkey's No. 1 import and export partner, while Turkey ranks 7th in the EU's top import and 5th in export markets, according to the European Commission.

Turkey is also getting substantial funding from the migrant pact.

But the rhetoric has soared quickly into no-return territory, and the dimming prospect of Turkey’s eventual EU membership means less leverage.

“Using the Nazi narrative is like the nuclear weapon of political language in Europe, you just don’t do that,” says Pierini, the former EU envoy. “If Erdoğan wins, basically you have one-man rule, a system without check and balances,” says Pierini. “This is 180-degrees from the European concept of liberal democracy, so essentially you have the accession talks going into irreversible coma.”