On Sunday morning, all the shops in my Istanbul neighbourhood had sold out of milk. In the supermarket, lactose-free was all that remained. In Turkey, that’s a sure sign that protest is afoot – demonstrators splash milk on their face to neutralise the sting of tear gas.

For the past week hundreds of thousands of Turks have gathered in cities across the country to protest the arrest of Ekrem Imamoglu, Mayor of Istanbul, who was detained in a dawn raid on 19 March. On Sunday, as the city’s milk sold out, he was formally charged with corruption offences (a separate terrorism case remains open) and transferred to the sprawling prison complex near Silivri, on the outskirts of Istanbul, to join thousands of other incarcerated opponents of President Recep Tayyip Erdogan. Hours later, he was formally nominated as the opposition’s candidate for the next presidential elections.

The timing is no coincidence. Imamoglu has emerged as Erdogan’s first real rival in two decades since he first won a shock victory in Istanbul in 2019. Since then, he has used his position at the helm of this city of 16 million to propel himself onto the national stage, touring the country to speak to rallies in the same bombastic, caustic style as Erdogan – both men hail from the Black Sea region, which is known for its religious, nationalist and macho culture. Before his arrest, Imamoglu had been travelling around the country as he campaigned for the presidential nomination; the next elections are scheduled for 2028, but may be called early.

Erdogan knows the playbook – he himself rose to national prominence as mayor of Istanbul back in the 1990s, when Turkey was dominated by a secularist cadre within the state and military. Erdogan, the Islamist rebel upstart, was jailed and expelled from his post after reciting a poem at a rally. The poem in question, penned by the Turkish nationalist poet Ziya Gokalp, referred to ‘minarets’ as ‘spears’, and compared ‘mosques’ to ‘barracks’, and was used to convict Erdogan on the charge of inciting violence and religious hatred. His incarceration turned him into an international figurehead for free speech, with Amnesty International speaking out in support of him. Within four years of his release, he was prime minister of the country – and he has never ceded power since.

And so, history repeats itself. Erdogan has swept away the old secularist dogmas, to the relief of many Turks, but he has also installed his own apparatus of repression in their place. Over the past decade, his democratic backsliding has accelerated: he has brought state institutions, the security services and almost all of the media under his control, and used all of them to keep winning at the ballot box. He has also talked of raising a ‘pious generation’ of Turks, and has expanded religious schooling to that end.

Now, however, that same generation is mobilising against him. Turks in their early twenties were children when the Gezi Park protests exploded in 2013 – too young to have taken part, although many of their parents did. Since then, Erdogan has launched waves of round-ups targeting actors, businesspeople and students accused of fermenting the Gezi Park movements, pushing thousands to flee the country while thousands more are languishing in jail.

Then, in 2016, a failed coup attempt against Erdogan opened the way for him to crack down further. Hundreds of thousands of soldiers, police officers, teachers, judges and other state workers have been dismissed from their posts, accused of plotting with terrorist organisations. For years, it seemed as though protest had died in Turkey: even the smallest gathering was outnumbered and quickly halted by riot police.

Today, a generation of Turks that has never protested before is taking to the streets, staying there even in the face of tear gas and rubber bullets. The protests are growing night on night, and the police are meeting them far more quickly and brutally than in Gezi in 2013. Riot police are firing continuous sprays of tear gas and water cannon over the crowds, kettling them into confined areas and beating some of those they catch. More than a thousand people have been arrested for taking part in the protests, on top of the 107 arrest warrants issued with the Imamoglu investigation.

Erdogan chose his moment to move; the arrest came after months of operations against other opposition mayors, journalists and businesspeople, none of which drew any condemnation from Turkey’s European allies. Donald Trump’s second term is proving a boon for autocrats everywhere, and as the US backs out of its role in the Atlantic alliance, Turkey’s leverage in Europe has soared. Erdogan has positioned his country as a key mediator between Russia and Ukraine, and an interlocutor to the new government in Syria. He is betting that his diplomatic clout will outweigh Europe’s concerns over the state of Turkish democracy, and so far he has been proven correct: although the Council of Europe and EU have condemned the crackdown, European governments have so far remained silent.

In another sense, though, his timing may be off. The sudden fall of Bashar al-Assad in Syria in December has reignited hope that the unthinkable may be within reach. There is little love between the Turks protesting today and the Syrians celebrating Assad’s end, but there are parallels between them: Erdogan’s pragmatic support base, like Assad’s, has been worn down by years of economic calamities and corruption, and his hold may be more fragile than it seems. In Serbia, too, where President Aleksander Vucic has followed Erdogan’s authoritarian blueprint, mass protests this month forced the resignation of the government (although not Vucic himself).

Turkey has now reached its own turning point. Just four months ago, Erdogan was celebrating the undignified fall of Assad, his great adversary. Now, as the protests of his pious generation grow, he may be starting to feel uneasy.