Yep - and The fact that there are still such weapons in Syria makes Russia complicit......
Which particular chemical weapons are we discussing?
Smouldering wood, used for gassing people in basements?
Chlorine - used in bulk for water treatment across the middle east?
Or nerve-agents, such as those used at Ghouta? Which were created by local fanatics using precursors smuggled in from Turkey.
I'm not seeing why the existence of these weapons would necessarily implicate the Russians.