Until you've met and talked to your entire nation, nationalism is a fairly nonsensical generalization and may lead you to dangerous - and very sloppy - thinking, in as far as it is divorced from actual subjective reality.
Such is the way of most sweeping generalizations. Let's not forget that the average American has only one testicle.
Most of the people on this board have more in common with each other, regardless of nationality, than with the majority of their "nation", who - let's face it - they've never actually talked to at all.
I've met lots of people from my nation who I hate, and lots from other nations who I like. It seems to me that the people of any nationality, if you talk to them, rather than exert a sense of nationalism, is made up of more or less the same mix of people I like and people I hate. Why then elevate any particular group as better - especially one that will inevitably include a larger number of people you hate?
Much better to treat everyone on a case by case basis, and throw the whole nationalism thing out as the dangerous nonsense it is.