From the fact that Britain is not an oppressed nation, it does not follow that Argentina is.
There is a fatuous conceptual blurring here, between the vague notion of an 'imperialised' nation (presumably, one weaker and subordinate within an international system dominated by powerful imperialist states), and an *oppressed* nation - one denied national rights by a foreign power. To regard an independent bourgeois state, with a relatively powerful bourgeoisie which has regional power ambitions, as an *oppressed nation* is to mangle the meaning of words.
We were not 'neutral' between the British and Argentine bourgeoisies in 1982. We were against both.