The Syrian government has placed its massive stockpile of chemical weapons under tamper-proof seals and destroyed its means of producing new chemical agents, meeting an international deadline for President Bashar al-Assad's regime, which continues to try and position itself as the most reasonable of Syria's warring parties.

The effort to change Mr. al-Assad's image got a further boost Thursday from news that efforts to convene a major peace conference in late November were collapsing because none of the main opposition groups fighting Mr. al-Assad's forces were willing to take part.

And so the remaking of "Bashar the Tyrant" into "Bashar the Reasonable" continues apace. Even the United States and France, powers that only months ago led calls for Mr. al-Assad's removal, now appear to accept that he will play a large part in Syria's future, with Washington and Paris pushing – so far unsuccessfully – for moderate rebels to join a proposed peace conference that would involve direct negotiations with Mr. al-Assad's representatives.

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All main rebel groups insist on Mr. al-Assad's resignation as a precondition for talks, and some of those close to the so-called Geneva II peace process now say the meeting likely won't take place before January.

Mr. al-Assad has said his government is ready to take part in the negotiations, but he told UN and Arab League envoy Lakhdar Brahimi this week that they could only succeed if there was an end to state support for what he called "terrorist groups" – a clear reference to outside aid received by rebels, primarily from Saudi Arabia and other Gulf Arab states.

Analysts say Mr. al-Assad's message – that he is a force for stability fighting against extremists with links to al-Qaeda – has changed less than his audience has. Many in the West now see the war the same way he does, thanks to the growing influence of jihadi groups among the rebels opposed to Mr. al-Assad.

Mr. al-Assad "seems more reliable at this point. And that's his objective – to present himself as somebody you can deal with – at the same time as he depicts the rebels and the rebel-held territories as Kandahar," said Joshua Landis, a Syria expert at the University of Oklahoma. "Every other word that comes out of his mouth in interviews these days is 'al-Qaeda.' And there's a bit of truth to it, which is what has so many people flummoxed."

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The Syrian leader has also benefited from the warming relationship between the U.S. and Iran, long the main regional backer of Syria. Prof. Landis speculated that the U.S. may be willing to drop its insistence on Mr. al-Assad leaving power in a quid-pro-quo exchange for progress in negotiations to halt Iran's nuclear program.

The diplomatic manoeuvring takes place against a background of ongoing bloodshed in Syria's multifront civil war, which has already claimed more than 100,000 lives and forced two million others to flee the country. A representative from Unicef said Thursday that the fighting has made it "very difficult indeed" for aid workers to respond to an outbreak of polio in the war-torn east of the country. Polio had been eliminated from Syria in 1999.

Ironically, it was by crossing a declared "red line" set by U.S. President Barack Obama that Mr. al-Assad gained the engagement with the West he has been seeking since the uprising against him began. A chemical-weapons attack that killed hundreds of people on Aug. 21 brought the threat of U.S. force, which only receded when Mr. al-Assad agreed to a Russian-led proposal to hand over his chemical weapons for destruction.

That process has so far moved swiftly and according to plan. The Organization for the Prohibition of Chemical Weapons (OPCW) announced on Thursday that it was "satisfied that it has verified – and seen destroyed – all of Syria's declared critical production and mixing/filling equipment" for chemical agents such as sarin and VX.

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The regime's store of 290 tonnes of chemical weapons, as well as a further 1,000 tonnes of chemical agents that can be used to manufacture weapons, have also been put under seals that an OPCW spokesman declared "impossible to break." Next is a mid-2014 deadline for the destruction of that stockpile.

The sealing of Syria's chemical stockpile takes a dangerous weapon out of the hands of Mr. al-Assad's forces, but it will do little to end the fighting, especially as the warring parties and their outside backers can't agree on the terms for beginning peace talks. Syria's allies Russia and Iran have agreed to take part in Geneva II, but there seems to be little point in holding the meeting unless at least some rebels attend.

While the U.S. and France have pushed for those affiliated with the secular Free Syrian Army to send envoys to Geneva, the West's influence over the Syrian opposition has been dramatically weakened since Mr. Obama's decision not to use force in response to the August chemical-weapons attack.

Many anti-Assad fighters have taken to YouTube to denounce the peace process and anyone who agrees to take part in the Geneva II talks. "There's been a shift away from the West and toward more extreme ideologies, because they're the ones supporting the Syrian uprising and the Syrian opposition," said Eliot Higgins, a British-based blogger who studies videos posted by Syria's warring factions.

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Saudi Arabia, which is a major backer of Sunni Islamist rebels fighting Mr. al-Assad, has also expressed its opposition to Iran taking part in any peace conference. In many ways, the war in Syria is now a proxy fight between Saudi Arabia, which sees itself as the centre of the Sunni Muslim world, and Shiite-dominated Iran, which has sent fighters to back Mr. al-Assad, whose family adheres to a sect of Shia Islam.

But Saudi Arabia, long a key U.S. ally, has seen its concerns take a back seat to efforts to encourage rapprochement between Washington and Tehran. International negotiations aimed at freezing or curbing Iran's nuclear program got a fresh start earlier this month in the first round of talks since the centrist Hasan Rouhani was elected president earlier this year.

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