In the context of Trump declaring himself I “nationalist” I would like to quote the prophetic words of George Orwell from his “Notes On Nationalism” written way back in 1945.
“Nationalism is power-hunger tempered by self-deception. Every nationalist is capable of the most flagrant dishonesty, but he is also — since he is conscious of serving something bigger than himself — unshakeably certain of being in the right . . . [Every nationalist] spends part of his time in a fantasy world in which things happen as they should . . .
One has no way of verifying the facts, one is not even fully certain that they have happened, and one is always presented with totally different interpretations from different sources . . . The general uncertainty as to what is really happening makes it easier to cling to lunatic beliefs. Since nothing is ever quite proved or disproved, the most unmistakable fact can be impudently denied. Moreover, although endlessly brooding on power, victory, defeat, revenge, the nationalist is often somewhat uninterested in what happens in the real world. What he wants is to feel that his own unit is getting the better of some other unit, and he can more easily do this by scoring off an adversary than by examining the facts to see whether they support him . . .
Some nationalists are not far from schizophrenia, living quite happily amid dreams of power and conquest which have no connection with the physical world.”
For more on what Orwell said: https://medium.com/@KeithDB/trump-declares-himself-a-nationalist-what-would-orwell-say-55c1bf711e6