Probably because they disagree with the degree to which nationalism was responsible for WWI or other wars. It’s worth keeping in mind that imperialism was probably more of a contributing factor, not to mention the Austro-Hungarian invasion of Serbia and the German invasion of Belgium, or the assassination of Franz Ferdinand.

In my view the positive aspects of nationalism, notably the rejection of foreign imperialism or colonial rule, or even more indirect forms of foreign domination, it’s contribution to popular democracy and republicanism, and the eradication of latent feudal relationships, are all positive things.

The use of organised violence predates nationalism and even liberal democracies have engaged in illegal wars of aggression, so it’s hard to understand why nationalism, in its broad sense (I’m not arguing it can’t be toxic or lead to violence), is singled out.

I think it was, or at least to my knowledge the earliest reference to the distinction between nationalism and patriotism that Macron recently put forward, made by Orwell, and I still think it’s an inane semantic distinction rooted far too greatly in ideolect.

Jingoistic patriotism has lead as many people to take up arms and kill other people as the belief in distinct nationalities.