Don’t know who downvoted you, you’re absolutely right. Just as an anecdotal example, my grandmother was an extremely intelligent and progressive Italian-American woman, but Columbus was the one thing she would never budge on. It goes back to a time when Catholics had to constantly defend their loyalty to America. I’d imagine St Patrick’s day was a similar thing. It was these immigrants’ single point of pride that other Americans would respect and understand.
Found the fascist!