Four years ago, a woman in her mid-thirties took to CNN to savage Israel’s offensive against Gaza in an impeccable English accent. “The Israeli barbaric assault on innocent civilians” was “horrific”, was her passionate plea; the numbers of dead “continuously increase”. Occasionally she seemed almost overwhelmed with emotion as she spoke of mothers unable to even give their children a glass of milk.

What rationalisations, what self-justifications must now be going through the mind of the Syrian dictator’s British-born-and-raised wife Asma al-Assad – notoriously described as a “rose in the desert” by Vogue magazine months before Syria’s uprising began? Perhaps she has other concerns: recent photos uploaded by the regime’s Instagram account reveal her wearing a Jawbone UP, an upmarket activity tracker that monitors meals, sleep and exercise. It is nearly two and a half years since her husband’s regime plunged Syria into an unspeakably brutal civil war by firing on what began as a secular movement for democracy: if Israel’s cruelty was “barbaric” and “horrific”, what words are left to describe her husband’s crimes? More than 100,000 dead, millions displaced, and now evidence pointing towards the firing of chemical weapon-laden missiles that suffocated families in their beds.

We don’t know the emotional response of this glorified gangster’s wife at children fitting and foaming at the mouth. Neither are we sure who fired the chemical weapons at eastern Damascus. Initial doubt that Assad’s thugs could be responsible were hardly the preserve of conspiracy theorists. Why would the regime unleash nerve gas just as UN weapons inspectors were checking into their hotel a few kilometres away? Why use them now as the dictatorship has gained the upper hand in the civil war? Why attract the threat of Western attack just as interest in Syria had waned, and the rebel forces had become so discredited? Have we not already established that al-Qa’ida elements – increasingly prominent on the rebel side – are capable of anything?

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But experts with no ulterior motive simply do not believe the rebels capable of unleashing such a targeted strike, even if they had the desire and possession of some chemical agents. Syria’s dictatorship has only just allowed the UN to inspect the site after dragging its feet. Attention has been drawn to Assad’s brother Maher, a notoriously sadistic general who once ordered troops to shoot unarmed protesters in the head and heart.

Whatever the truth behind this unforgivable crime, the likelihood of some form of Western intervention is greater than ever, as David Cameron, Barack Obama and France’s foreign minister Laurent Fabius have made clear. The Cruise Missile Liberals, who casually call for other people’s children to fight their wars and for bombs to fall on the heads of those they will never meet, are beginning to cry for military action. It is perplexing indeed: these are the sorts of people who generally favour bombs to be dropped on the sorts of Islamist fighters taking on Assad’s forces. But it is a perfectly human response to look at toddlers in bodybags and want to do something. No dictatorship is a legitimate form of government – it is a gang of thugs whose violence begins with depriving the people of the right to choose who rules them.

But Western intervention would surely be disastrous. When protesters first took to the streets of Damascus, they were heavily secular and democracy-orientated. There are still such elements, such as the Syrian Democratic People’s Party. But rebel forces have become increasingly taken over by Islamic fundamentalists, bolstered by prestige in their courageous fighting and aid from wealthy Gulf elites. It is the region’s Western-backed fundamentalist monarchies such as Saudi Arabia who have armed the rebels. Remember Abu Sakkar, the rebel commander filmed cutting out and apparently eating the heart of a government soldier while ranting against Syria’s Alawite minority? His forces, the Farouq Brigades, are actually among some of the more moderate Islamist groupings.

There are now two powerful al-Qa’ida groupings operating. One is Jabhat al-Nusra, originally a spin-off from al-Qa’ida in Iraq, a resurgent movement responsible for some of the worst atrocities in the neighbouring country’s sectarian bloodbath. It took the first provincial capital, the city of Raqqa, earlier this year, giving it huge sway in the country’s north-east. It swiftly imposed strict Islamist laws, intimidating women and smashing up shops selling alcohol. Then there is ISIS, an even more zealous al-Qa’ida formation that has fired on secular protesters and harassed the civilian population of Aleppo. A “civil war within a civil war” beckons: members of the Farouq Brigades have spoken of a second revolution against al-Qa’ida if Assad falls, and Free Syrian Army Military Council member Kamal Hamami was allegedly killed in July by such elements. No wonder many of the secular Syrian activists who first took the streets now fear the revolution has been hijacked, and even fear the fall of Assad.

There is a frightening precedent. In the 1980s, Western arms to Afghan jihadis were funnelled by the Pakistani secret services to the most radical groups. When the Soviet-backed Afghan regime fell in 1992, the victorious rebel groups collapsed into internecine conflict, reducing Kabul to rubble and leading many to welcome the Taliban as restorers of order.

Iraq’s government fear that a Syrian opposition takeover would plunge Lebanon and Iraq into civil war. The conflict has already contributed to Iraq’s descent back into chaos: more than 1,000 died in the country in July, the highest toll since 2008. An attack could invite retaliation from Iran and an escalation of Russian’s support for Assad’s thugs, helping to drag the region even further into disaster.

And then there’s the legacy of Western intervention in the region. The West props up numerous Middle Eastern dictatorships, including the fundamentalist House of Saud. Bahrain’s pro-democracy activists are battling a Western-backed dictatorship, and in 2011 suffered a tacitly Western-backed Saudi invasion. Western protests over the Egyptian’s junta massacre of the Muslim Brotherhood were muted indeed, and the US provides the military with $1.2bn of annual aid. US drone attacks provoke widespread fury. The Iraq war led to a sectarian bloodbath, Western crimes such as the use of white phosphorous in flattened Fallujah and a shift in regional power that favoured Iran. The US were driven out of Lebanon in the early 1980s and Somalia in the early 1990s. Twelve years on, Afghanistan remains an intractable, bloody mess. Libya is often cited as a rare success story but – despite being infinitely less complicated than Syria – it led to horrendous atrocities against black Libyans, and the country is now an anarchic state ruled by militias on the brink of conflict.

It would be perverse indeed if the West ended up the de facto allies of al-Qa’ida, though it would mark a return to a disastrous dalliance with international Islamic fundamentalism. There’s no question that those who use chemical weapons must be arraigned in an international court. But a UN-brokered peace process involving all the local and regional players remains the only solution. It may not satisfy the understandable impulse that “we have to do something”. After all, throwing water on a chip-fat fire is “doing something”. Syria’s nightmare looks as if it could not get worse: the truth is it could, with calamitous consequences for the whole Middle East.