“More than 2,000 fighters from Russia and ex-Soviet republics are in the territory of Syria. There is a threat of their return to us. So, instead of waiting for their return, we are better-off fighting them on Syrian territory.” This was Vladimir Putin, justifying air strikes by his forces in Syria.

We have also heard: “Isil [Isis] leaders have threatened America and our allies. Our intelligence community believes that thousands of foreigners – including Europeans and Americans – have joined them in Syria and Iraq. Trained and battle-hardened, these fighters could try to return to their home countries and carry out deadly attacks. I know many Americans are concerned about these threats. I want to tell you that the United States of America is meeting them with strength and resolve.” So said Barack Obama, justifying air strikes on Syria and Iraq.

And then there was David Cameron. “There was a terrorist directing murder on our streets. I am not prepared to stand here in the aftermath of a terrorist attack on our streets and have to explain why I did not take the chance to prevent it when I could have done so. So I took decisive action to keep Britain safe,” he said, justifying air strikes in Syria to kill two British jihadists.

Not much difference in the sentiment and intent there, one would have thought. But the Kremlin’s military intervention in Syria has been presented in the West as part of a strategic offensive, as in Ukraine, to undercut Nato’s influence and destabilise its allies. In other words, “it’s all about us”.

A picture depicting Russian President Vladimir Putin is splattered with eggs during a protest against Russian military operations in Syria, in Istanbul, (AP)

In reality, there are a whole range of issues driving Russian policy. Standing up to the West, as the Kremlin sees it, is just one of these. The demands of geopolitics has ensured that Syria has become an international arena, as the killing of the Iranian Brigadier General Hossein Hamedani near Aleppo on Thursday once again showed.

Nato’s answer, the much publicised announcement of increasing the size of its reaction force from 12,000 to 40,000, is irrelevant as far as Ukraine and Syria are concerned. The force will not be deployed for fighting in Ukraine, which is not a member of Nato, and certainly not in Syria. As a member state Turkey can ask for help under Article 5 of the Alliance’s treaty, but with the second-largest land force in Nato, it does not need troops.

A $500m (£326m) flagship American plan which was supposed to produce 5,000 fighters who would operate in Syria, from “moderate” rebels was quietly abandoned on Friday. It had proved a disaster, with fewer than 60 ready for the field. A separate American-trained group, the 30 Division, handed its weapons to the al-Qaeda-affiliated Jabhat al-Nusra.

So we return to depending on an air war to counter the Syrian terrorist threat. The fact remains that if Britain and America are vulnerable to attacks by returning jihadists, then so is Russia, and the threat it faces is from an enemy far more implacable than those who had travelled from Western Europe and North America.

One of the two Britons killed in a British drone strike in Syria, Reyaad Khan, was plotting terrorist acts in Britain, said Mr Cameron. We understand that telephone calls had been tracked in which he had talked about various bombing plans last summer, none of which came to anything. No claim was made that the second Briton killed, Ruhul Amin, was involved in terrorist plots in the UK.

There are a relatively small number of American nationals with the Islamists in Syria. One, calling himself Abu Muhammed al-Amriki, has posted “selfies” with prominent commanders. He was particularly proud of one with Abu Omar Al-Shishani, the northern commander of Isis.

In pictures: Russian air strikes in Syria Show all 19 1 /19 In pictures: Russian air strikes in Syria In pictures: Russian air strikes in Syria Syrian boys cry following Russian air strikes on the rebel-held Fardous neighbourhood of the northern embattled Syrian city of Aleppo Getty In pictures: Russian air strikes in Syria Russian defense ministry spokesman Major General Igor Konashenkov speaks to the media in Moscow, Russia. Konashenkov strongly warned the United States against striking Syrian government forces and issued a thinly-veiled threat to use Russian air defense assets to protect them AP In pictures: Russian air strikes in Syria Syrians wait to receive treatment at a hospital following Russian air strikes on the rebel-held Fardous neighbourhood of the northern embattled Syrian city of Alepp Getty In pictures: Russian air strikes in Syria Russian Deputy Defense Minister Anatoly Antonov speaks at a briefing in the Defense Ministry in Moscow, Russia. Antonov said the Russian air strikes in Syria have killed about 35,000 militants, including about 2,700 residents of Russia AP In pictures: Russian air strikes in Syria Jameel Mustafa Habboush, receives oxygen from civil defence volunteers, known as the white helmets, as they rescue him from under the rubble of a building following Russian air strikes on the rebel-held Fardous neighbourhood of the northern embattled Syrian city of Aleppo Getty In pictures: Russian air strikes in Syria Civil defence members rest amidst rubble in a site hit by what activists said were airstrikes carried out by the Russian air force in the town of Douma, eastern Ghouta in Damascus, Syria Reuters In pictures: Russian air strikes in Syria A girl carrying a baby inspects damage in a site hit by what activists said were airstrikes carried out by the Russian air force in the town of Douma, eastern Ghouta in Damascus, Syria Reuters In pictures: Russian air strikes in Syria Civilians and civil defence members look for survivors at a site damaged after Russian air strikes on the Syrian rebel-held city of Idlib, Syria Reuters In pictures: Russian air strikes in Syria Civilians and civil defence members carry an injured woman on a stretcher at a site damaged after Russian air strikes on the Syrian rebel-held city of Idlib, Syria Reuters In pictures: Russian air strikes in Syria Volunteers from Syria Civil Defence, also known as the White Helmets, help civilians after Russia carried out its first airstrikes in Syria In pictures: Russian air strikes in Syria The aftermath of Russian airstrike in Talbiseh, Syria In pictures: Russian air strikes in Syria Smoke billows from buildings in Talbiseh, in Homs province, western Syria, after airstrikes by Russian warplanes AP In pictures: Russian air strikes in Syria Russian Air Forces carry out an air strike in the ISIS controlled Al-Raqqah Governorate. Russia's KAB-500s bombs completely destroy the Liwa al-Haqq command unit In pictures: Russian air strikes in Syria Caspian Flotilla of the Russian Navy firing Kalibr cruise missiles against remote Isis targets in Syria Â© TASS/ITAR-TASS Photo/Corbis In pictures: Russian air strikes in Syria Russia claimed it hit eight Isis targets, including a "terrorist HQ and co-ordination centre" that was completely destroyed In pictures: Russian air strikes in Syria A video grab taken from the footage made available on the Russian Defence Ministry's official website, purporting to show an airstrike in Syria In pictures: Russian air strikes in Syria A release from the Russian defence ministry purportedly showing targets in Syria being hit In pictures: Russian air strikes in Syria Russia launched air strikes in war-torn Syria, its first military engagement outside the former Soviet Union since the occupation of Afghanistan in 1979. Russian warplanes carried out strikes in three Syrian provinces along with regime aircraft as Putin seeks to steal US President Barack Obama's thunder by pushing a rival plan to defeat Isis militants in Syria In pictures: Russian air strikes in Syria Caspian Flotilla of the Russian Navy firing Kalibr cruise missiles against remote Isis targets in Syria, a thousand kilometres away. The targets include ammunition factories, ammunition and fuel depots, command centres, and training camps Â© TASS/ITAR-TASS Photo/Corbis

Born Tarkhan Batirashvili in Georgia of an Orthodox Christian father and a Chechen Muslim mother, Shishani led Jaish al-Muhajireen wal-Ansar, a group of around 3,000 fighters with a large contingent from the Caucasus, who earned the reputation of being the toughest and most violent among the rebels.

This is the terrorist threat facing Russia. Shishani had taken part in the short war against the Russians five years ago as a sergeant in the Georgian army. He had also fought the Russians in Chechnya. He has repeatedly declared, since arriving in Syria, that he and his men will return to take revenge on Russia. Other Chechen-led groups – Ajnad al-Kaykaz, Junud al-Sham and Tarkhan’s Jama – have also vowed to carry out attacks on Russia. None of these three is part of Isis, but aligned with “moderate” rebels. They are positioned outside Latakia, a stronghold of the Alawite community of Bashar al-Assad, the ally Russia is trying to save.

Three years ago, in the run-up to the Sochi Olympics, Prince Bandar bin Sultan, the then head of Saudi intelligence, allegedly threatened Mr Putin that Chechen Islamists would be activated to carry out attacks in Russia unless the Kremlin stopped its support for Assad. The Prince was rebuffed by a furious Russian President, and soon afterwards Prince Bandar was relieved of the Syria brief by the Saudi King. Shishani had been well trained in combat by US forces while in the Georgian army – he was described at the time as an extremely able soldier.