When Cyprus got its independence from the British empire in 1960, three countries were given the job of guaranteeing the constitution that laid down how power should be shared between Greek-Cypriots and Turkish-Cypriots: the United Kingdom and the two "mother countries", Greece and Turkey. These guarantors had the right and duty to intervene if the terms of the deal were violated.
The power-sharing deal collapsed in 1963, mainly because a large number of Greek-Cypriots wanted union with Greece. The Turkish-Cypriot minority fled into dozens of isolated enclaves, and in 1964 the United Nations sent in the UNFICYP peacekeeping mission to protect them. But none of the guarantors intervened.
Ten years later, in 1974, the colonels who ruled in Athens organised a bloody coup in Cyprus that overthrew the elected government and installed a regime committed to unite the island with Greece. When Britain, the other guarantor, refused to act against the coup, Turkey sent troops on its own.
Greek-Cypriot resistance collapsed in a few days, and Turkey occupied more than one-third of the island. All the Greek-Cypriots in the Turkish-occupied zone fled south, and all the Turkish-Cypriots in the rest of the island abandoned their besieged communities and fled north. And that's how it has remained for the past 43 years, with UNFICYP patrolling the buffer zone between the Republic of Cyprus and the TRNC.
Finally, four years ago, both parts of the island managed to have governments that were in favour of reunification at the same time. There was broad agreement between them on a federal republic with wide autonomy for the two communities, and so the conference in Switzerland began last month with high hopes.
Why was the Greek-Cypriot side finally ready for a deal? (The last time a roughly similar deal was on the table, in 2004, the Turkish-Cypriots voted in favour by two-to-one -- and the Greek-Cypriots voted against it three-to-one.) The answer is probably money.
A reservoir of natural gas worth an estimated US$50 billion has been discovered on the seabed off Cyprus's coast, but it cannot be developed so long as the seabed rights are potentially in dispute. Turkey itself has no claim, but it could certainly provide powerful backing if the Turkish Republic of Northern Cyprus were to demand a share of the revenue.
It was Turkey that killed the hopes for a final deal in Switzerland. President Recep Tayyib Erdogan holds absolute power only by grace of a referendum in April that he won by a mere one per cent margin -- and he only got that by monopolising the media coverage and fiddling the results.
The 49 per cent of Turks who voted "No" against expanding Erdogan's powers see him, quite rightly, as the end of real democracy in Turkey, so he needs to wrong-foot them and keep his own supporters mobilised by inflaming public opinion with various nationalist grievances. This time it's Cyprus.
Turkey refused to give up its right to intervene in Cyprus under the 1960 agreement, or to withdraw the 35,000 soldiers it keeps stationed in the TRNC. So the deal collapsed, and it will be a long time before anybody tries again. If ever.
But in the circumstances, it is very unlikely that the United Nations will pull its peacekeepers out.
Gwynne Dyer is an independent journalist whose articles are published in 45 countries