Using your logic, then it does not make any sense to prosecute any crimes in the US. I mean, if you put to death a murderer, and there are still a few thousand people who will commit murders, then why bother ?
Apples and oranges. The question isn’t how to stop all murders, but whether a military action that could lead to a confrontation with Russia was justified. Degrading production of chemical weapons would not be sufficient justification, because chemical weapon materials are remarkably easy to make under very primitive conditions. “International honor”? HA!
The only conceivable justification would be that it degraded chemical weapons delivery capabilities, which an air strike could do, but this air strike did not necessarily do. According to Mossad’s damage assessment, it mattered hardly at all, if that. So all that’s left is “international honor”. HA! and again HA! in that case. At least they tried to do something militarily relevant in order to deter, while “upholding” international “honor”. That’s the best I can say.
And the whole thing could have been a prearranged kabuki dance for the media, with Russia and Trump...ah...colluding in this instance, and if the alleged chemical attack was really a false flag, that might have been the right thing to do.