Russia’s affair with Turkey has been blossoming for decades – why has it taken the west so long to pay attention?

To diplomats in London, Washington, Paris and Brussels, it’s Turkey that is the belligerent actor. It has defied Nato rules by buying Russian weaponry, part of a pattern of Ankara drifting away from western norms under president Recep Tayyip Erdogan.

To much of Turkey, it’s the west that has betrayed it, writing off its security concerns and European aspirations because of surging Islamophobia.

But there is another pattern at work in Turkey that many observers on both sides have missed, one that is familiar to those that have watched the Balkans and eastern Europe over the last few years.

It’s the same pattern through which the Russians have captured key elements of former vassal states – even members of the European Union and Nato – with strategic business deals in key sectors and political alliances as part of what scholars have called the “Kremlin Playbook”, Moscow’s method for turning economic power into political influence and strategic advantage in countries like Bulgaria, Hungary, and Serbia.

The United States last month kicked Turkey out of the programme to build and deploy advanced F-35 fighter jets after Ankara ignored Washington’s warnings and began taking delivery of Russian S-400 missile defence systems. In recent days, dozens of Turkish pilots and military personnel training on the F-35s in the US were forced to return home.

More sanctions may be coming, as mandated by the US congress. Some in Washington, angered by Turkish behaviour on a number of regional domestic issues, argue for even stronger punishments.

That’s music to the ears of Vladimir Putin.

For the Kremlin, Turkey is a cherished prize. Russia has worried for centuries about free passage through the straits of Bosphorus and Dardanelles, through which its Black Sea warships and mercantile vessels can access the rest of the world. Even now, Russia complains when even a new buoy appears along the narrow Bosphorus which cuts through Istanbul.

During the Cold War, Turkey was firmly within the Nato orbit, a militantly capitalist state ideologically opposed to the communist experiment to the north as well as instinctively fearful of Russian imperial ambitions.

But all the old rules and calculations changed after the Soviet Union’s collapse.

A former western diplomat described how Russia’s state-owned Gazprom seduced Turkish officials in the late 1990s into signing the Blue Stream gas pipeline deal that bypassed transit countries. The US argued against it, but Turkey signed anyway. Among the tools in Russia’s arsenal was a private jet filled with prostitutes, according to the former diplomat.

Like in the Balkans, Russia has also sought out investments in both the telecommunications and banking sectors. Sberbank, run by a Putin ally, bought Turkey’s Deniz Bank, using it for years as a conduit to evade sanctions, but is withdrawing, likely after realising such investments offer neither strategic leverage nor massive returns within Turkey’s competitive and relatively transparent finance and communications sectors.

Turkey and Russia agreed to form a joint $1bn investment fund this year, in what represents another attempt to solidify the ties between the two countries.

But for Russia, the real strategic power play in Turkey is neither the S-400 deal, the investment fund, or Russian citizenry’s modest investments in real estate. It’s in the energy sector.

Russia’s Gazprom and Turkey are building yet another pipeline across the Black Sea, Turkstream, which will further tighten the bonds between the two countries and allow Russia to bypass Ukraine.

Russia’s state-owned Rosatom is building Turkey’s first nuclear power plant in Akkuyu, along the country’s southeastern shores. Russia won the contract for the plant in 2010 over a number of rival firms. Construction began last year.

But it was the amendments to the deal quietly slipped into the contract in March and published in the official Turkish gazette that hints at the Kremlin’s strategic aims, and show how Ankara is being snookered the same way as say Bulgaria, or other victims of Russia.

The original deal allowed Rosatom and its Turkish partner to build factories, warehouses, commercial enterprises, administrative buildings and other buildings at the site. But construction kept being stalled, until Ankara came back with new terms.

Under the amended deal, Rosatom is fully in charge of the Akkuyu power plant project and can bring in any staff they want and even demand more land.

Rosatom can now build sea ports and terminals. It can conduct shipping, and offer port services, including storage, loading, unloading, forwarding, and transporting of goods.

Russian presidential aide Yuri Ushakov told the daily Kommersant last year that Rosatom secured takes breaks on Akkuyu for 90 years.

“It seems that the Russian government, which already signed a fantastic deal for Rosatom, is also getting a port, owned, operated and controlled by Russia, and staffed by Russians,” said Yoruk Isik, a Russian foreign policy specialist in Istanbul.

“Given the location of Akkuyu, these tiny changes might offer a very strategic logistics base for [the Russian military’s] global and regional operations or whatever other way Russian government will see it serves its interest,” he said.

It was the ongoing war in Syria and the 2016 coup attempt in Turkey, that gave the Kremlin its opportunities in Turkey.

Millions of Syrian refugees already live in Turkey, driven there by waves of Russian-backed military campaigns that target civilian populations. Russia controls the spigot of destabilising Syrian refugees flowing into Turkey, and Ankara knows it.

Putin was also among the first foreign dignitaries in Ankara after a failed 2016 coup which many Turks believe was supported or at least tacitly approved of by the west.

Like a spymaster recruiting a disgraced rival sobbing in the pub, the former KGB officer found Erdogan at his most vulnerable and offered him a helping hand. “The Russians know how the Turkish mind works,” said Isik.