When the Emperor Justinian entered the newly-built Hagia Sophia in 537, its imperial patron congratulated himself: “Solomon, I have surpassed thee.” As he ordered that the great building be returned to the status of mosque, which it had gained at the Ottoman conquest in 1453 and lost in 1934, Turkey’s President Erdogan must have thought, “Ataturk, I have reversed thee.”

Every Turkish school child knows that the decree turning the Byzantine masterpiece into a museum was issued on the same day that the Turkish government awarded Mustafa Kemal his new surname, “Ataturk” – “Father of the Turks”. If the most symbolic act of Ataturk’s secular republican regime can be reversed today what else of his legacy is under threat?

Westerners have a tendency to dismiss symbols as, well, merely symbolic, just as saying something is history means it is dead and gone. Not only Turks but all their neighbours, Muslim, Christian and Jew alike, know that symbolic acts are potent and history still has bite.

Invoking the spirit of Sultan Mehmet II – “The Conqueror” – as Erdogan and his media have done repeatedly has contemporary resonance in Turkey in a way that William the Conqueror has long since lost his cultural grip here. In the official version of history, he is only the conqueror of Constantinople and converter of Hagia Sophia into a mosque. The Sultan who read Greek and Latin and had himself portrayed by Gentile Bellini and enjoyed a drop is “un-history” to loyal backers of President Erdogan. They prefer the jihadi warrior as their model and that worries the neighbourhood.

As if the anti-Israeli aspect needed emphasising, Hamas hurried to endorse Erdogan’s decision

In his comments justifying bringing prayers and sermons back into the Hagia Sophia in accordance with the Sultan’s will, President Erdogan emphasised that this was just the start, “The resurrection of Hagia Sophia [as a mosque] follows the express will of Muslims throughout the world” paving the way “for the liberation of Al Aqsa” in Jerusalem. Even before he spoke the crowd gathered outside the building had chanted, “Next to Jerusalem”. As if the anti-Israeli aspect needed emphasising, Hamas hurried to endorse Erdogan’s decision.

President Erdogan’s bad relations with Israel are notorious but his actual ability to put into practice the “liberation” of the Muslim holy places there must be in doubt. Maybe his vocal backing for the right to land of the radical wing of Palestinian politics will remain rhetoric. But at sea, Turkey and Israel are increasingly at odds.

Ankara is trying to redefine the national boundaries in the Mediterranean  so that it can scoop up natural gas and other resources as its own. Cyprus, backed by Greece and Israel oppose this. Drilling rigs risk becoming pawns in any assertion of sovereignty by the navies of either side.

Like it or not, Cyprus is next door to Turkey and the northern half of the island is its annexe if not yet annexed. More dramatically,  and extending Turkey’s reach far from its own shores, Erdogan signed a deal with the Tripoli government in Libya that agreed on the use of vast swathe of sea between them as their waters. In return, Erdogan has sent generous military aid to the Tripoli side in its war against the insurgent Haftar in Benghazi.  Erdogan has extolled Turkish military casualties in Libya as “martyrs” in the tradition of the Ottoman warriors who served there from the sixteenth century until the war against Italy in 1911.

Ataturk fought in that war and saw it as emblematic of the Ottomans’ waste of resources better spent on the core Turkic lands. Time and again in recent years Erdogan has referred to the Ottoman military heritage in neighbouring states from the Balkans via the Middle East to North Africa as an obligation to intervene to defend them (whether they want defence or not, it seems). Whereas Ataturk insisted after his victory over the Greeks in 1923 that the Turkish Republic wanted “nothing more and nothing less” than its new borders, Erdogan is playing with fire far beyond them.

The Turkish President is not only aggressively asserting Turkey’s energy interests in the Mediterranean against regional rivals like Greece, Cyprus and Israel, but he seems to enjoy squaring off against France in particular as his major opponent as puppet-master of the other side in the Libyan war. President Macron has done him the compliment of saying he is “playing a very dangerous game.”

France as a secular republic inspired much Ataturk’s legislation and system of government. The Kemalists were Turkish Jacobins at home making root-and-branch changes to dispose of the Ottoman old order but they showed no inclination to spread their revolution abroad like the French “armed missionaries” of the  1790s. Erdogan rejects that secular legacy and its French roots but now he is playing the role of “armed missionary” on behalf of the Muslim Brotherhoods like Hamas across the Middle East. That is why governments from Egypt to the Gulf as well as in North Africa (for all their own flaws) fear Turkey is set on forcing its preferred model of Islam and society on them.  Turkey’s military power is formidable. Its Bayraktar drones which have turned the tide of war in Libya are produced by a company run by the President’s son-in-law. Ankara’s military-industrial complex is a family affair but no less effective for that.

One thing Erdogan has in common with some of his Ottoman predecessors is that acts with the caprice of a sultan. Not only have domestic political allies who had seemed ideological blood brothers suddenly found themselves axed but foreign allies too can wake up to find that yesterday’s profusions of solidarity have dissipated and been replaced by snarling condemnation.

Under Erdogan Turkey has gone from model moderate Muslim darling of the EU, modelling his party on Germany’s CDU he said, to the worst nightmare of Europe and Germany in particular where he stages election rallies as if Cologne was a suburb of Istanbul. He has veered from dog-fights with Russia to collusive friendship with President Putin, though changing the status of Hagia Sophia has offended Russian Orthodox believers who form a key support group for the Kremlin. As for NATO, Turkey’s buying of Russian anti-aircraft missiles designed to shoot down  US planes has set alarm bells ringing in the Pentagon.

If Erdogan is a loose cannon, who has been on the losing side in Syria even if he seems to have the upper hand in Libya, will he stumble into a wider conflict? The standoff between French naval vessels and Turkish ones recently saw radars locked on to targets. A misstep could lead to casualties and war.

Despite recent domestic political setbacks, appealing to national pride as well as Muslim sentiment has proved a potent elixir for Erdogan as he was struggling in the polls with a sluggish economy helping the opposition to victories in the big cities in municipal elections. The fact that the main Turkish opposition parties and many “liberal” intellectuals endorsed the Hagia Sophia decision illustrates the potency of this synthesis between Islamic revivalism and neo-Ottoman Turkish nationalism. Although it is commonplace to say that young Turks are secular and indifferent to religion, Erdogan has seen that they are frequently nationalistic and if he associates religion with national assertiveness a broad spectrum of them will back him in conflicts abroad.

If Turkey’s economic problems worsen, the temptation  to play the victorious Sultan routing unbelievers and heretics may prove too strong. A strong army and a weak economy don’t make for a quiet life for the neighbours.