>>3515013 lb
And this is where your lack of education is showing. (I'm not being sarcastic or making fun of you.)
Learn what common law is, and how it relates to our history. It used to be taught in schools.
Now, directly to your question: Can the federal government make it illegal for a Kansas resident to murder another Kansas resident in Kansas (and not on federal property)? Why or why not? When you have the answer to that, you'll have your answer to why a constitutional amendment was needed to outlaw alcohol.