If you want to go into it, read Fanon, especially “The wretched of the earth”. It explains well the need for national liberation movements to define themselves as a nation outside of the perspective of their colonizers for the first time, and how important it is to break away from the views that the oppressor imposes on the oppressed in order to build a post-colonial project.

That can often look as what has been characterized as nationalism, but it springs from a different material condition, one of opposition and struggle to colonization, unlike bourgeois nationalism which hinders working-class international solidarity in the name of big-power competition