To be less general, to be more defined, to better or in the first place explain mechanisms, all just different ways to say "You will have to explain that better if you want to convince me".
So as I thought what it comes down to is that you find my POV simply not convincing.
Please simply say so next time instead of blabbering about analytical frameworks.
But I gladly follow suit.
The tribe may appear central because it makes my sweeping generalizations plastic and concrete + offers evolutionary and by extension emotional explanation of the nature of group identities. What I mean by tribe? Well in all actuality the word only serves as an umbrella term for all kind of groups of natural size (i.e. everyone knows each other or perhaps even better the size of a group our brain is said to be able compute in a way so to see all members as individuals, something in the range of 100 - 300 members give or take, don't remember the exact findings) and which act as a unit.
That can be a group of hunter and gatherers or a small ancient community or a soccer team. All those groups act as one and develop a group identity and tend to think of themselves as special in some or another way. They develop their own folklore, customs etcetera.
Now note that a group which does not act as one does not do that or to much lesser extent. And the more unity, the more they do that.
A school class less so than a soccer team, a soccer team less so than a group of hunter and gatherers.
Now why is that so? I think the answer is evident: Those things emotionally bound the members of a group and hence strengthen the group as a whole. The greater the unity of the group, the greater do the members depend on each other to make the group function hence the stronger the emotional bound should be.
What all that tells me is that humans who are part of a unit naturally seek to identify with this unit. And the thing now is that we can witness the workings of this every single time in every single unit of whatever scale. Be it tribes or city-states or nations. They are all units as they act as one. And they all do the same general stuff tribes do with regards to group identity.
Before nationalism, states were often very ununited. The peasant did not depend on the peasant in some other village, there was no relation. All what united them was the will of the ruling class. In the wake of nationalism, this unity rapidly grew for which I would name two main reasons:
(1) Economic development which increased interdependencies and means of communication
(2) Something I shall label philosophical development: I.e. the idea that the members of the unit state actually mattered (democracy), which of course requires those members to get organized = greater unity (though I suppose for a Marxist (2) can not be separated from (1), which I may agree with)
So why should we just extrapolate the inner workings of a tribe to unnatural big groups up to states of millions? Because observation/history says it gets extrapolated.