Political Memes

Nationalism when taken to the extreme can be bad because it's extreme, but there's nothing inherently wrong with nationalism.

What you just described, this "mild nationalism?" There's a word for that: patriotism. Nationalism is extreme patriotism.

Nationalism: an ideology that elevates one nation or nationality above all others and that places primary emphasis on promotion of its culture and interests as opposed to those of other nations, nationalities, or supranational groups

-Merriam-Webster Dictionary

And when nationalism becomes even more extreme, it becomes chauvinism or jingoism.

Chauvinism: undue partiality or attachment to a group or place to which one belongs or has belonged; excessive or blind patriotism; an attitude of superiority toward members of the opposite sex

Jingoism: extreme chauvinism or nationalism marked especially by a belligerent foreign policy

When Hitler promised to build a wall around Germany to keep immigrants from diluting German culture during his campaign, that was nationalism. American isolationists were/are nationalists.

The Republican Party in the 90s and 2000s was a nationalist party bordering on chauvinism. The party of Trump is a jingoist party that hits every definition of chauvinism at the same time.