The Man Who Shot Liberty Valence
https://en.wikipedia.org/wiki/The_Man_Who_Shot_Liberty_Valance
Lyrics: https://genius.com/Gene-pitney-the-man-who-shot-liberty-valance-lyrics
Gene Pitney's hit song (Audio with static pics, YewwToob) https://www.youtube.com/watch?v=vDN4L7cAQf0
Yes, the HERO was an armed American. But the BAD GUY is also an armed American, and a murderous criminal, NAMED LIBERTY. You're missing the entire point: The movie uses the cookie-cutter American Western, full of American values, to subtly push the idea that Liberty (by name) has to be killed off.
EDIT: Why not name the Bad Guy something else? ANYTHING else other than "Liberty?"