For a brief gleaming moment in 2013, in the midst of the horrific Syrian war, the United States and Russia prevailed upon the Syrian government of Bashar al-Assad to sign on to the 16-year-old Chemical Weapons Convention. Chemical weapons were actually removed from Syria – some, at least.
Since then, there have been rumours and reports of new chemical-weapons attacks. Now, the United Nations and the Organization for the Prohibition of Chemical Weapons have verified three such attacks in Syria.
The Syrian government has got around the Chemical Weapons Convention by concealment and lying. It has hidden industrial chlorine gas inside barrel bombs. Mind you, barrel bombs themselves are terrible, too; they are improvised, unguided bombs that can fly out in any direction at all – but they have not yet been banned by any international convention.
Mr. al-Assad and his colleagues are not alone in the region in engaging in chemical warfare. The OPCW has confirmed that ISIS has used another chemical weapon, sulphur mustard.
ISIS has the advantage of not being a member of any international organization at all. Why would it be? Abu Bakr al-Baghdadi claims to be the Caliph of the whole world; he and his colleagues have only disdain for all other states and regimes.
Back in 2013, the United States and Russia were on relatively good terms. Today, with an intense struggle for Mosul, and relentless bombing of Aleppo, President Vladimir Putin seems less disposed to co-operation with the Western powers on chemical weapons or anything else.
Still, the Russians surely don't want the Assad family to have a significant stock of nightmarish weapons of their own. They want influence over minor powers; they don't want to distribute any extremely dangerous gifts – or to tolerate ISIS having them.
ISIS is spreading reports that it has a large stockpile of chemical weapons, but American intelligence doubts that it's true. One toxic stockpile may have literally gone up in smoke.
The permanent members of the United Nations Security Council are not now on the best terms, but they should still co-operate to restrain reckless, toxically desperate forces in the volatile Middle East.
Editor's note: The original version of this editorial incorrectly referred to a chemical weapon detected in Syria, sulfur mustard, as a "gas." This is a corrected version of the editorial.