Sri Aurobindo describes this matter in detail in his writings on the Human Cycle. No doubt Internationalism is the future of man but to rush prematurely towards it would only mean the hegemony of few powerful nations over the rest of humanity under the garb of globalisation and internationalism. This would crush out many beautiful things that each nation has to contribute leaving a big vacuum in our evolutionary groupings. Each nation, like an individual, has its own unique soul which must be brought out and work together for the good of the world. Each nation must discover its own spiritual roots to nourish its individuals.
A rash internationalism may well end up with a few nations once again dominating the rest since human nature has hardly changed since the two great wars. Just as an individual is not to be abolished by the family but nourished by it and vice versa so too the nation unit is not to be abolished by the growing spirit of internationalism and collectivism but mutually nourished. This is the big challenge before humanity at present. That is why we see nature giving rise to fresh waves of nationalism.
Of course there is a dark and dangerous turn that nationalism may take but that is true of almost everything. Internationalism itself can become a menace for the world when seized wrongly. Humanity may unite egoistically and exterminate other species that it perceives as harming it or even try reaching out to alien beings and imagine itself in war with them. Let the roots of evil, that is the human ego disappear and all these temporary scaffolding and partial resting grounds of humanity will disappear without effort leaving only that which has the divine sanction and stands on grounds of Truth rather than holy sentiment.
About Savitri | B1C3-10 The New Sense (pp.29-31)