The European Union faces a pressing problem as it decides how to handle another major slide towards autocracy in Turkey. So far, the signs are not good.

Over the past decade, core democratic institutions have been systematically eroded in Turkey, under the rule of Recep Tayyip Erdoan, who has been in power since 2003. Media freedom, independent judiciary and civil society have all been targeted. A major turning point came in 2016, when Turkey abandoned its parliamentary democracy in favour of a hyper-centralised presidential system. Since then, the national parliament has been marginalised and nearly all checks on executive power have been eroded.

While elections in Turkey have not been fair for many years, they were at least free. According to the international observers, elections were not fair as President Erdoan and the ruling parties enjoyed "unjustified advantage". However, elections still could offer voters a "choice between genuine political alternatives" - providing citizens with a sliver of hope for democratic change.

That era may have ended on March 19, with the arrest of Ekrem mamolu, Istanbul's mayor. mamolu was on the cusp of being made the opposition's presidential candidate and was widely seen as Erdoan's main electoral rival. He now looks unlikely to be able to stand for president. This is not just a blow to the opposition but potentially indicates the end of free elections in Turkey according to some observers.

All this has been happening in the EU's immediate neighbourhood. Indeed, it has been happening in a country that remains, at least nominally, a candidate for EU membership. Yet Brussels has largely remained silent. This silence may prove a strategic mistake.

The EU's reaction to mamolu's arrest has been, at best, cautious. Ursula von der Leyen, president of the European Commission, issued a carefully worded expression of "deep concern". The spokesperson for the EU echoed a familiar refrain, saying that as a candidate country, Turkey must "uphold democratic values".

In their joint statement Kaja Kallas, high representative of the European Union for foreign affairs and security policy, and Oliver Varhelyi, commissioner for enlargement, struck a similarly cautious tone. They said Turkey is "expected to apply the highest democratic standards and practices".

Only the European parliament, long considered the flagbearer of the EU's values, adopted a more direct stance. Several political groups openly criticised Turkey during the plenary session on April 1. A delegation led by the European parliament first vice-president Katarina Barley visited mamolu in a symbolic gesture of support.

But these expressions of concern and acts of solidarity with mamolu have not been matched by any credible action or condemnation potent enough to have a deterrent effect on the Turkish government. As many observers have noted, the EU's strategic interests have increasingly overshadowed its commitment to democratic principles.

It is no secret that the EU has never had a coherent strategic vision on Turkey. In a prime example of the transactional nature of the relationship, the EU outsourced refugee challenge to Turkey in 2016 in exchange for financial aid to Ankara. It was a deal driven not by long-term goals but short-term pragmatism.

Today, in an era of growing geopolitical instability, Turkey has only become a more critical partner for the EU. Ankara commands the second-largest army in Nato, boasts a rapidly advancing defence industry, and has ample experience in peacekeeping and out-of-area operations. These are all increasingly valuable as the US, under Donald Trump, retreats from European security.

Turkey has also become a key player in Syria after the fall of Bashar al-Assad. With strong political and economic ties to the new leadership in Damascus, Turkey started to play a central role in Syria's reconstruction, as well as in its energy and defence sectors. Working toward the stabilisation and reconstruction of Syria is a shared interest for both Brussels and Ankara. For both sides, potential collapse of Syria involves major security concerns, including further refugee inflows to Turkey, and via Turkey to Europe, the proliferation of armed groups, jihadist terror and the spillover of regional instability.

And while the containment of Kurdish groups in Syria is a priority for Ankara, the control of ISIS militants in detention in Northern Syria is a priority for the EU. Brussels has recognised Turkey's "essential role to play in stabilising the region", adding to the growing list of areas of common interest.

Add in the fear of destabilisation in the EU's immediate neighbourhood, and it becomes clearer why Brussels might prefer "stability" under Erdoan over the uncertainty of post-Erdoan period.

But failing to stand up to Turkey now is a mistake - and one with long-term consequences. The EU should care about what is happening in Turkey, not just for the sake of Turkish democracy, but for its own security. How it responds has implications for the credibility of the European project itself.

Seeking closer security and defence cooperation with Turkey, in the absence of a shared understanding of fundamental values between Ankara and Brussels, is not realistic. As Hungary's stance toward Russia since the full-scale invasion of Ukraine in 2022 has shown, if there is no agreement on core values, aligning strategic interests becomes increasingly difficult. Turkey is a self-confident and assertive regional power, and it will not hesitate to follow a foreign policy that could ideologically diverge from that of the EU.

Turkey's recent foreign policy decisions illustrate this perfectly. Its actions in the eastern Mediterranean, northern Syria before Assad's fall, Libya and the Caucasus demonstrate its readiness to pursue a more assertive path without consulting western partners. A prime example of this was Turkey's decision to purchase S-400 missile defence systems from Russia, which created interoperability problems with Nato allies.

Moreover, autocratic ideas tend to be contagious. When a country follows a more illiberal trajectory, it affects its wider neighbourhood. Turning a blind eye to Turkey's authoritarian turn while cooperating on security and defence matters risks legitimising Erdoan's governance model. This could further strengthen the illiberal axis in the region.

Finally, the EU risks alienating democrats and younger generations in Turkey. Despite the ups and downs in EU-Turkey relations, Turkish citizens have consistently shown strong support for the EU. Maintaining this momentum is not just an ethical responsibility or a matter of credibility for the EU - it is also a long-term investment in building a more democratic, trustworthy and stable neighbour.