Turkey and Saudi Arabia have been told that, if they start a local war with Russian forces in Syria, they will have to fight it alone. So this is probably the end
Earlier this month, the Turkish Government, in league with Saudi Arabia, made a tentative decision to enter the war on the ground in Syria — and then got cold feet about it. Or more likely, the Turkish Army simply told the Government that it would not invade Syria and risk the possibility of a shooting war with the Russians.
The Turkish Government bears a large share of the responsibility for the devastating Syrian civil war. From the start, Recep Tayyip Erdogan, then Prime Minister and now President, was publicly committed to overthrowing the Syrian regime of Bashar al-Assad. For five years he has kept Turkey's border with Syria open so that arms, money and volunteers can flow across to feed the rebellion.
Mr Erdogan's main ally in the task of turning Syria into a Sunni-ruled Islamic State (allthough 30 per cent of Syrians are not Sunni Muslims) is Saudi Arabia. Together these countries and some smaller Gulf states worked to subvert the original non-violent movement in Syria that was demanding a secular democracy, and then armed and supplied the Sunni-dominated armed rebellion that replaced it.
The US Government also wanted to see Mr Assad's regime destroyed (for strategic reasons, not religious ones). So for years, Washington turned a blind eye to the fact that its allies, Turkey and Saudi Arabia, were actually supporting the extremists of the Islamic State and the Al-Nusra Front, Al Qaeda's franchise in Syria.
largely as a result of that support, these two extremist organisations now completely dominate the Syrian revolt against Mr Assad's rule, accounting for 80 per cent to 90 per cent of the active fighters. Turkey and Saudi Arabia finally broke their ties with the Islamic State last year, but they still back the Al-Nusra Front, which has camouflaged itself behind an array of minor “moderate” groups in the so-called “Army of Islam”.
When the Al-Nusra Front, with increased Turkish and Saudi support, over-ran much of northwestern Syria last spring, Russia finally went to the aid of its long-standing ally, the Syrian Government. Russian air power helped the Syrian Army push back the troops of both the Al-Nusra Front and the Islamic State, and Mr Erdogan was so irked by this that he actually had Turkish fighters shoot down a Russian bomber last November.
It was clear at the time that the Turkish Army was unhappy about the prospect of a military clash with Russia. It does not share Mr Erdogan's dream of an Islamist-ruled Syria either. So the Russian bombs kept falling, the Syrian Army went on advancing, and now it has cut the main supply line from Turkey to the rebels in and around Aleppo.
This would also have allowed the Turkish Army to whack the Syrian Kurds, who are building a de facto independent state in the Kurdish-majority territory along Turkey's southern border. (Mr Erdogan is already at war with Turkey's own Kurdish nationalists, having broken a four-year truce with them last summer.)
On February 13, the Turkish Army began shelling Syrian Kurdish forces, and on February 14, the Assad Government objected to the UN about a hundred “Turkish soldiers or mercenaries” who had crossed the border into Syria. At which point the grown-ups took over, and the Turkish Defence Minister denied that there was any intention to invade Syria.
France publicly warned Turkey to end its attacks, and there were doubtless secret but frantic warnings to the same effect from Turkey's other North Atlantic Treaty Organisation allies. Turkey (and Saudi Arabia) have almost certainly been put on notice that if they choose to start a local war with Russian forces in Syria, they will have to fight it alone. So that is probably the end of that, and everybody can get back to the business of partitioning Syria — which is what all the talk of a ‘cessation of hostilities’ is really about.