Garvan Walshe is a former National and International Security Policy Adviser to the Conservative Party.  He runs TRD Policy.

If you’re a political obsessive who’s been unable to tear yourself away from the news on holiday, and if the endless Covid coverage hasn’t sapped your will to read, you may have chanced upon some alarming headlines, reporting Greek and Turkish ships colliding, France sending warships to the Eastern Mediterranean, and even the United Arab Emirates, fresh from its rapprochement with Israel, hinting it would base fighter jets in Crete.

An August geopolitical crisis is, after all, what 2020 has been missing – but seeking to resolve it also presents a rare opportunity for the UK to rebuild its diplomatic capital.

Greek newspapers have taken on jingoistic hue, and are calling for foreign powers to intervene against Turkey, with the French deployment presented as a response to Athens’s appeal. To complete the nineteenth century-flavoured picture, Ankara has drawn support from Berlin, with the lumbering US Secretary of State, Mike Pompeo, playing Bismarck to the uninterested Kaiser in the White House.

This crisis brings together four elements, overlooked by a distracted United States, and an EU paralyised by its two inveterately anti-Turkish members (Greece and Cyprus): the treaty of Lausanne, signed 99 years ago as the Ottoman Empire disintegrated; the evolution of the international law of the sea, which has made that treaty even more favourable to Greece than was thought at the time; the Libyan civil war, soon to reach its tenth year after the overthrow of Gaddafi, and the discovery of new gas reserves.

Signed as part of the post-World War I reordering of the world, the Treaty of Lausanne set limits to the expansionism of modern Greece, which had been accumulating territory at the Ottoman Empire’s expense since its independence in the 1820s, and involved a then-fashionable population exchange between 1.3 million Greek-speaking Orthodox people living in and around Smyrna (Izmir) and 400,000 Muslims from Greece.

If Greece lamented the loss of Smyrna, granted ot them by the Treaty of Sevres only a year earlier, to the new Turkish Republic, Turkey was stuck with accepting permanent Greek control of islands a mile or two off its own coast.

Yet, at a time when states only enforced territorial limits at three miles, and freedom of navigation was allowed on the high seas, this was a price that could be paid. But the development of international practice to include a 12-nautical mile limit would severely impede Turkish freedom of navigation out of the Dardanelles.

Turkey and Greece, naturally, have different interpretations of whether the islands in the Aegean are capable of generating their own territorial limits (islands can, in principle; but if they form part of a country’s share of the continental shelf, then they do not extend it any further). International law is ambigious, and the ICJ has declined to resolve the matter.

Matters were further complicated by the introduction of “Exclusive Economic Zones” (which featured, incidentally in the Falklands War), whereby states can assert the right to regulate economic activity within 200 miles of their coastlines.

EEZs are reasonable when states share an ocean littoral, like the US and Canada, but are hard to demarcate for narrow seas like the Mediterranean. The UN Convention on the Law of the Sea does a fat lot of good here, stating only that the conflict should be resolved on the “basis of equity and in the light of all relevant circumstances.”

This was how things stood before the Arab Spring, but the Libyan civil war, in which Turkey and Italy back the internationally recognised government, while Egypt, France and Russia backed rebels led by General Haftar – and the discovery of large gas reserves at a point in the Eastern Mediterranean some 400 miles wide.

Taking advantage of its alliance with Tripoli, Turkey conjured up an EEZ between itself and Libya, giving itself access to gas near Crete. Greece then responded by manufacturing its own EEZ with Egypt, to deny Turkey access to the same waters.

American neglect is to blame for the absurdity of two NATO members returning to nineteenth century-style diplomatic rivalry. A fully engaged United States would not have allowed the situation to deteriorate this far. It would have understood that the discovery of gas in contested waters would spur a scramble for it, and therefore a mechanism for sharing the spoils to avoid conflict would have to be set up.

Only Washington has the clout to bring such a process to a successful conclusion, but this is an area in which Brexit has enhanced Britain’s diplomatic position. No longer an EU member, the UK is now in a position to act as an honest broker between Greece, Turkey and the other interested regional powers, and begin to forge a mechanism to regulate gas exploration in this increasingly volatile region. What better initiative for a part-Turkish Prime Minister whose father has a house in Greece?