I think you may have quoted the wrong thing. The section you highlighted above states that clothing was fumigated with the same gas later used by Nazis to exterminate prisoners, it makes no mention of it being a way to “medicalize” or make exeuctions “humane”.

Again, I’m not American so I’d appreciate it if you highlighted how this is related to “American Liberaism” which you initially criticised. As it is it appears you’re assuming whatever actions the someone in power in America takes is “American Liberalism”, I’m not sure that’s something I agree with.