Those rollicking jihadists, the Syrian rebels, love a joke: although they can be deadly serious – such as when they’re eating the internal organs of their enemies – what they enjoy more than anything is a really good prank. There was the time they claimed the Assad regime was killing babies in incubators – not very original, but hey, it worked for the Kuwaitis! Then there was the "massacre" at Houla, which was alleged to have killed 32 children and over 60 adults: a photo started appearing in the mainstream media, documenting the slaughter. The state-supported BBC was first to run with it – until it was discovered the supposedly incriminating photo was taken in Iraq during the recent war. The photographer was justifiably furious, the story was withdrawn, and the Syrian rebels went back to the drawing board.

I could go on for quite a while about the various Syrian hoaxes we’ve been subjected to, but let’s get down to the latest one – a claim Syrian government forces used nerve gas at the Syrian village known as Ghouta. Videos posted by the rebels show rows of people killed or incapacitated without any dramatic indications of physical trauma: instead, the victims display convulsions and other signs of exposure to asphyxiating gases.