I use ‘west’ most frequently because it’s the shortest. Sometimes I even just say, ‘they’, if the context makes it clear that I’m talking about the bourgeoisie. But you’re right, for most purposes these are synonyms.

I think ‘west’ falls down the most when talking to liberals because it’s a bit antidialectical. It’s natural opposite is ‘east’. While everyone seems to understand that Australia, New Zealand, and Japan are included in ‘west’, it makes much less sense to refer to LatAm, Africa, Asia, etc as the ‘east’. Indeed, it makes so little sense that I don’t think anyone means that. But if they don’t mean that, then ‘west’ is being used as a static, isolated category. And individual liberal workers feel called out when we say ‘west’, but the real target is the west-as-the-beating-heart-of-capitalism. When talking with liberals, we need to insist on the relational aspect of our terms.

In that situation, it’s more helpful to say global north, which does presuppose a global south. And developed, which presupposes ‘underdeveloped’. On this one, though, care is needed. Liberals use developed/developing, in part because their liberal sensibilities tell them it’s rude to say that another people/state/etc is underdeveloped. It implies inferiority.

To be clear, liberals think developing countries and the people who live in them are inferior, but liberals don’t like it when you point this out. Liberals like to imply that (1) to be capitalist is to be civilised, (2) some countries are ‘developing’ (i.e. towards capitalism), (3) it is possible for developing countries to become developed, (4) if some countries are still developing, they have not yet arrived at capitalism, hence they must be uncivilised, but (5) liberals pretend not to be racist, so they cannot admit this.

You might say, but you get to the same conclusion if ‘developing’ is replaced with underdeveloped and, anyway, liberals admit this, redtea! They explicitly use this logic as justification for IMF, World Bank, and WTO restructuring. It’s even included in the highest forms of international law, right there in black and white! In this case, the liberal animal may be pretending that every so called developing nation will one day be developed if only [insert an incredibly racist reason as to why underdeveloped states are underdeveloped].

‘Underdeveloped’, unlike ‘developing’, raises the questions, why and by whom? The ruling class does not want you to ask, nevermind answer, these questions.

By rejecting the liberal framework and using developed-underdeveloped, we can point out that no underdeveloped country will ever develop for so long as the west (hello old friend) keeps stealing the resources and labour, destabilising governments, assassinating progressive (or even effective, successful, or independent) leaders, holding them down with unpayable IMF debt, and insisting that all tech must be imported (not allowing the locals to grow their own high-tech industries, which, you know, makes it almost impossible to develop).

Liberals have also tried to do something similar, with making ‘third world’ a dirty word. For them, it’s not a dirty word because it’s rude to people in the third world (although this is what they will tell you), it’s a dirty word because it insists that there are global divisions and that, unlike liberals have been claiming since Fukuyama, history is not yet over. The existence of a third world reveals the lie behind the claim that if every country is capitalist, it’s only a matter of time before they all become developed.

In sum, it depends on the context. But whatever the context, the underdeveloped third world will have it’s glorious day once more.

Edit: typos