If a country needs to overly emphasise an ideal, that’s usually because that ideal doesn’t apply in that country (“Land of the free”, “Democratic people’s republic of …”).
If a person needs to subscribe to patriotism, it’s usually because they have never accomplished anything better in their life than being born in a specific place.
I don’t think there’s anything inherently wrong with being proud of impersonal achievements. If one of your parents did something considered pretty great, I think it’s generally fine to be proud of it, even though you had no agency in being born to them.
As with anything, though, it’s very possible to take it to the extreme. If an achievement or value becomes your entire personality and you begin to actively disparage others on the basis of not-being-that, as you said, that’s when I call it one of the bad “-isms.”
I see nationalism as a range within that of patriotism, but starting at that extremist point.