In late 2017, President Recep Tayyip Erdogan made the first visit to Athens by a Turkish leader in his lifetime – and started firing off accusations. Greece would never have joined Nato without Turkey’s support, he claimed, adding that Athens fails to respect Turkey’s borders and neglects hundreds of former Ottoman sites. A groundbreaking <a href="https://www.thenationalnews.com/world/europe/2023/12/08/turkey-and-greece-want-to-be-an-example-to-world-by-building-closer-ties/" target="_blank">visit</a> turned into diplomatic shock treatment, paving the way, in part, for roiling tensions that led to confrontations in the eastern Mediterranean and put the two neighbours on the brink of war in mid-2020. Of course, Turks and Greeks <a href="https://www.thenationalnews.com/opinion/comment/2022/06/14/turkey-and-greece-love-to-quarrel-thats-unhelpful-and-dangerous/" target="_blank">have been quarrelling</a> since ancient times. A few decades of calm followed Turkish independence and the 1923 population exchange, but then came anti-Greek violence in Turkey in 1955; Turkey’s <a href="https://www.thenationalnews.com/opinion/comment/is-a-two-state-cyprus-a-real-possibility-1.1206048" target="_blank">invasion of Cyprus</a> in 1974 and the island’s division; and more war drums in 1987 and 1996. But this latest period of unrest may have come to an end last week when Mr Erdogan, six years to the day since his last visit, returned to Athens to meet Greek Prime Minister Kyriakos Mitsotakis, agree to a dozen new initiatives and sign a friendly relations declaration. “There is no issue between us that is unsolvable,” said Turkey’s longtime leader. “We want to turn the Aegean into a sea of peace.” Few seas have seen as much trouble as the Aegean, but the Athens Declaration seems a good start – urging the two states to maintain regular communication, find ways to co-operate militarily, and double annual trade to $10 billion. Also, several of the bilateral initiatives hint at real progress. To help further stem illegal migration, Turkey and Greece committed to an unprecedented exchange of security personnel. Greek coastguard officials are to be posted in Izmir, on Turkey’s Aegean coast, while Turkish coastguard officials set up shop in Lesbos. After years of back-and-forth accusations about migrant pushbacks and other violations, this could be a game-changer in terms of security co-operation. In another landmark move, Greece agreed to allow Turkish citizens without visas to enter its Aegean Islands. Tourist-friendly islands like Chios, Samos, Lesbos and Kos are visible from Turkey and hundreds of kilometres from the Greek mainland, yet most Turks have been unable to visit them because they lack Schengen visas. At a time when Turkey is openly challenging Nato expansion and accusing the West of barbarism and Islamophobia and prominent observers are calling for Turkey to be kicked out of Nato, this marks a sharp U-turn in Ankara’s relations with the West. How did it all start? The tenor began to shift after Greece responded to Turkey’s devastating February <a href="https://www.thenationalnews.com/mena/2023/02/24/death-toll-from-turkey-and-syria-earthquakes-surpasses-50000/" target="_blank">earthquakes</a> by quickly dispatching rescue teams. Shortly after that, Turkey responded in kind when Greece suffered a horrific <a href="https://www.thenationalnews.com/world/europe/2023/03/01/greece-train-crash/" target="_blank">train crash</a>. Yet in June, as their defence ministers talked of improving relations, Mr Erdogan <a href="https://www.thenationalnews.com/opinion/comment/2023/06/22/a-triumphant-erdogan-could-make-turkey-a-much-more-demanding-nato-member/" target="_blank">denounced Athens’ weapons purchases</a> from the US and said Turkey sought to “contain its adversaries”. The neighbours <a href="https://www.thenationalnews.com/opinion/comment/2023/05/30/can-the-leaders-of-turkey-and-greece-calm-the-aegeans-troubled-waters/" target="_blank">could not even agree</a> on what to call the sea that separates them, thanks to Turkey’s tourist campaign promoting a place called Turkaegean. Athens said the label put Greek sovereignty over its Aegean Islands in doubt, so to now see Greece welcome Turkish border officials to those same islands, six months later, is surprising to say the least. But there’s still a long way to go. Neither is likely to back down from their positions and the two sides do not even know how to start talks on issues like Cyprus and maritime borders. In both countries, few issues exercise the electorate like going after the rival across the Aegean. Also, it’s wise to wonder if it’s mostly for show. In an interview with a Greek newspaper last week, Mr Erdogan said the continental shelf issue is a “dispute that can be brought to The Hague.” But flying back from Athens a few days later, he told reporters that the two neighbours could resolve their issues without any third parties. If Turkey and Greece are able to shrug off their feuding history and begin solving most, or at least some, of their disagreements – a massive “if” – the impact could be profound. Normalisation would boost trade and tourism just as Greece is seeing a revival and Turkey shows signs of emerging from its years-long economic crisis. Annual foreign investment in Turkish bonds crossed into positive territory last week for the first time since 2017, for instance, and Turkey’s central bank reserves hit a record high of $140 billion. It could pave the way for meaningful Cyprus talks and the <a href="https://www.thenationalnews.com/opinion/comment/2022/08/16/could-turkey-change-the-course-of-energy-supplies/" target="_blank">development of natural gas</a> around the island, helping energy-hungry Europe. It could enhance Nato co-operation in the increasingly tense eastern Mediterranean and reduce anti-Turkey sentiment in Washington and Brussels, where that view <a href="https://www.thenationalnews.com/opinion/comment/2023/09/26/how-much-of-bob-menendezs-alleged-corruption-drove-us-turkey-policy/" target="_blank">tends to be driven</a> by pro-Greek voices. Finally, along with the major step Armenia and Azerbaijan took towards peace last week, Turkey-Greece amity would represent a glimmer of stability in a region sandwiched by brutal and globally impactful conflicts to the north and to the south. Now is not the time for more confrontation; if Mr Erdogan and Mr Mitsotakis are able to cement this budding friendship and calm the <a href="https://www.thenationalnews.com/opinion/comment/2023/05/30/can-the-leaders-of-turkey-and-greece-calm-the-aegeans-troubled-waters/" target="_blank">Aegean’s long-troubled waters</a>, it would be one fewer urgent item on the regional agenda. A sea of peace is always good for the world.