According to Tagore since nationalism emerged in post religious laboratory of industrial-capitalism it was only an organization of politics and commerce that brings harvests of wealth or carnivals of materialism by spreading tentacles of greed, selfishness, power and prosperity or churning up the baser instincts of mankind and sacrificing in the process the moral man, the complete man to make room for the political and commercial man the man of limited purpose.
Nationalism is not a spontaneous self-expression of man as social being where human relationships are naturally regulated so that men can develop ideals of life in cooperation with one another but rather a political and commercial union of a group of people in which they congregate to maximize their profit, progress and power. It is organized self-interest of people where it is least human and least spiritual.
Tagore deemed nationalism a recurrent threat to humanity because with its propensity for the material and the rational, it trampled over the human spirit and human emotion. It upsets man's moral balance obscuring his human side under the shadow of soul less organization.
Tagore called into question bot the constructed aspect of nationalism which stifled the innate and instinctive qualities of the human individual and its over emphasis on the commercial and political aspects at the expense of man's spiritual and moral qualities. Both these limitations reduced nationalism to an incomplete, monolithic and unipolar ideology essentially inadequate for human beings given to an inherent multiplicity and seeming contraries that needed to be unified and synthesized through a process of soulful negotiation and striking of an axial line between opposites to create the wholesome person.
Tagore also found the fetish of nationalism a source of war, hatred and mutual suspicion between nations. He argued that British colonialism found its justification in the ideology of nationalism as the colonizer came to India and other rich pastures of the world to plunder and so further the prosperity of their own nation. They were never sincere in developing colonized countries as to convert their hunting grounds into cultivating fields would have been contrary to their national interest. They thrived by victimizing and violating other nations.