Is the Syrian government using chemical weapons?

Syrian man alleged to be a victim of a nerve gas attack on Sheikh Masoud in Aleppo on 13 April - YouTube video posted by doctor. A doctor shot a video of an alleged victim of a Syrian nerve gas attack on 13 April in Aleppo

So has the Syrian Government crossed a US-declared "red line" by using chemical weapons against rebel forces or civilians in Syria or not?

The answer according to senior US figures seems to be a "well, maybe".

US Defence Secretary Chuck Hagel is reported to have said that US intelligence agencies can confirm "to some degree of varying confidence", as he put it, that Syria has used chemical weapons.

But the White House has been quick to follow up by warning that such assessments are not enough.

In a letter to congress Miguel Rodriguez, the White House director of the office of legislative affairs, says: "Given the stakes involved and what we have learned from our own recent experiences, intelligence assessments alone are not sufficient. Only credible and corroborated facts that provide us with some degree of certainty, will guide our decision-making."

Reticence

So what is going on here? It seems that western governments have a pretty good idea that chemical weapons have been used in Syria but are reluctant to say so, with the reticence strongest in the United States.

Mr Hagel's remarks are the first real chink in that reticence.

So why the caution? In part it may be due to the need to have sufficient quantity and quality of evidence to make an absolutely cast-iron case against Damascus.

Syria's chemical weapons

  • The CIA believes Syria has had a chemical weapons programme "for years and already has a stockpile of CW agents which can be delivered by aircraft, ballistic missile, and artillery rockets"
  • Syria is believed to possess mustard gas and sarin, a highly toxic nerve agent
  • The CIA also believes that Syria has attempted to develop more toxic and more persistent nerve agents, such as VX gas
  • A report citing Turkish, Arab and Western intelligence agencies put Syria's stockpile at approximately 1,000 tonnes of chemical weapons, stored in 50 towns and cities
  • Syria has not signed the Chemical Weapons Convention (CWC) or ratified the Biological and Toxin Weapons Convention (BTWC)

Sources: CSIS, RUSI

The potential consequences of a determination that the Assad regime has used such weapons are enormous.

But here of course there is a second problem. Setting red lines and warning of dire consequences if they are crossed is all very well, but what should actually be done?

With all the talk of "red lines", was Washington threatening a major air attack against Syria's extensive chemical weapons infrastructure if weapons were used?

Is the US really ready to become directly involved in the fighting against Mr Assad's government? Or has the Syrian president simply called Washington's bluff.

These are not simply political points. The US and its allies have been down the road of embarking upon armed conflict on the basis of uncertain evidence before in Iraq. The test of proof this time has to be much higher. And perhaps with the exception of that Israeli general, Washington's allies are reluctant to put the Obama Administration on the spot until the evidence is both incontrovertible and clear.

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