It is interesting, how chemical weapons are used for manipulation. It is like, it doesn't matter if you lay waist to an entire city, like Raqqa in Syria or parts of Mosul in Iraq. It is not much talked about in the western media. On the other side, even if it makes no sense for Syrian government to use chemical weapons and all the sense, if terrorists use it, such incidents are used for excusing attacks on Syria. Somebody figured out, chemical weapons usage has a bigger emotional impact and therefore uses it for manipulating the public into supporting military agression. Or, in the case of former Russian agent Skripal, into supporting more sanctions against Russia.