What chemical weapons have been used in Syria - if any?

摘要

The US has had a change of heart: its government is now reasonably confident that the Syrian military has used chemical weapons, specifically sarin, But things stitl don't add up. On 24 April, US defence secretary Chuck Hagel dismissed chemical weapons claims as "suspicions", However, on 25 April, in a letter to US senators, a White House spokesman said that US intelligence has decided "with varying degrees of confidence, that the Syrian regime has used chemical weapons on a small scale".