The Russian government/military
still aren't saying what gas they used to immobilize the kidnappers and kill over 100 of the hostages. There are probably two reasons that the hospitals who are trying to treat many of the hostages still don't know what was used: (1) it's a military secret and (2) it's a chemical that they don't have any experience with, so knowing what it is wouldn't help them.
Before we criticize the Russians for using military chemical weapons and for not telling the hospitals what they used and for initially lying about what killed the hostages, we need to ask whether the US would have done exactly the same thing. I assume that the answer is yes.