No,
Nationalism means you identify as a citizen of (insert nation here), and feel that the needs of your nation is more important than others. Anyone who is patriotic, also support nationalism to varying degrees. And anyone who says they aren't a nationalist of their country, answer me this question: IF the world is about to be flooded, or starved out or etc....except for one country, would you chose it to be your country that isn't starved out/flooded/etc...? If so, you just exhibited nationalism. You put your countries interests above others.
Anyone who is a patriot of their nation, also exhibits nationalism. It's retarded how people seem to consider nationalism as a bad thing.
Definition of nationalism btw: "identification with one's own nation and support for its interests, especially to the exclusion or detriment of the interests of other nations"
Also, I also see nothing wrong with putting the interests and needs of your own country above others. I mean, Poland sure as hell isn't going to do anything for me. Neither is Germany, Hungary, France, Austria, Mali, or any other nation. Only the U.S., so why wouldn't I prefer that my nation got its way over others? I benefit from it. Otherwise, I lose, or gain nothing at all. Nationalism is a good thing. It's only bad when leaders who are in a position to turn it into a military arm, begin to weaponize it. And even if its weaponized, I'd still say it depends on the circumstances as to whether it is a negative thing or not.