Con Coughlin and Editorial Comment:

Moscow’s determination to protect Assad at all costs is increasingly harmful to its own global interests

Ever since Russia embarked on its military adventure in Syria, Vladimir Putin’s relationship with Syrian dictator Bashar al-Assad has been characterised more as a marriage of convenience than an ideological meeting of minds.

Russia’s principal interest in Syria’s seven-year conflict has been to protect its military bases at Latakia and Tartus, which Moscow regards as being vital strategic assets. It was to safeguard the bases that Mr Putin agreed to a request from Iran, the Assad regime’s main regional backer, to intervene in Syria in the autumn of 2015, when it looked as though the rebels were about to capture Damascus.

So far as Moscow is concerned, keeping Assad in power must always be seen through the prism of protecting Russia’s interests in the region, rather than there being any great affection for the Ba’athist cause.

There have even been a couple of occasions when the Kremlin has intimated it might be prepared to ditch Assad and replace him with a candidate more palatable to the West, so long as it did not mean compromising Russian interests.

If this is the case, then it begs the question why Mr Putin remains so determined to defend Assad when the rest of the civilised world now views the Syrian leader as a pariah who should stand trial for committing war crimes.

Mr Putin’s continued support for the butcher of Damascus, moreover, seems all the more remarkable when all the evidence indicates the Assad regime carried out its devastating chemical weapons attack on Idlib last week without even bothering to inform Moscow about its intentions. For any other country, this would be its diplomatic get-out-of-jail card, a valid excuse to abandon an alliance because the conduct of one of the parties was no longer tolerable.

And yet Mr Putin continues to stand by the Syrian dictator, even though, by so doing, he runs the risk of deepening Moscow’s ostracism from the rest of the world.

Part of the explanation for Mr Putin’s stubborn refusal to abandon Assad lies with Russia’s problematic relationship with Damascus, which dates back to Cold War days, when having a foothold in Syria really was important because America enjoyed dominance throughout the rest of the Middle East.

During this period Russia helped the Syrians to develop their chemical weapons arsenal – which no doubt explains why Moscow has been so keen to take a lead role in decommissioning the deadly warheads. The Russians were supposed to have done this in 2013 as part of an agreement to prevent the Obama administration launching air strikes after the Assad regime was accused of using chemical weapons against rebel positions in the suburbs of Damascus.

Yet, as recent events in Idlib have demonstrated, the Assad regime has clearly retained some of its arsenal. This means it has duped the Kremlin on at least two counts: failing to come clean about its chemical weapons, and failing to inform the Russians of the regime’s intention to use them in attacks on rebel-held positions.

Given the scale of the Assad regime’s betrayal of their Russian protectors, the Kremlin would be well within its rights if it decided to abandon the support that has been instrumental in keeping the Syrian dictator in power – a point US Secretary of State Rex Tillerson will no doubt want to raise during today’s talks in Moscow. As Donald Trump remarked to Theresa May yesterday, there is “a window of opportunity” to persuade Moscow that “its allegiance with Assad in no longer in its strategic interest”.

That may be so, but Mr Putin shows no sign of ditching his alliance with Damascus. On the contrary, Moscow has mobilised its fake news propaganda machine to refute intelligence pointing to the Assad regime’s involvement in the Idlib attack.

By so doing, though, Mr Putin runs the risk of increasing Russia’s isolation. The only other country that shares the Russian leader’s enthusiasm for propping up Assad is Iran, whose own interest in developing weapons of mass destruction has attracted renewed interest from Washington. The Iranian-backed Islamist terrorist group Hizbollah is another organisation that has joined Moscow in condemning the US missile strikes on Syria.

Otherwise, Mr Putin finds himself very much on his own in his determination to keep the Assad regime in power at all costs. He has, in effect, dug himself into a big diplomatic hole, which cannot be good for Russia’s own interests.

Mr Tillerson may be able to break the impasse today by offering a compromise, such as getting Moscow to end its support for Assad in return for playing a prominent role in deciding Syria’s post-Assad future. But if Mr Putin insists on clinging to his deranged ally in Damascus, then Russia under his leadership will remain a lost cause.

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