A drive for equal economic and social opportunity underpins the left’s social programme of open borders so that people from economically disadvantaged nations can gain access to a First World lifestyle and wealth.
A world without borders is envisaged by much of the left.
However it is possible to close the wealth gap between nations (abolishing Third World debt for example), First World nations taking in those genuinely fleeing persecution in their own countries with on-shore processing, and to maintain nation state borders and nation state sovereignty.
The human seems to be a ‘territorial’ animal – especially under the capitalist mode of production, and whilst inhuman nationalism needs to be reeled in, nation states, currently in some ways, may tend to provide a sense of belonging and territory, and they can or should act as a humane power-break on centralised capitalist world government institutions such as the World Bank and International Monetary Fund which currently and largely fuel, perpetuate and ingrain more inequality between nations.
The nationalist arms-race needs to be carefully deconstructed as it is ultimately a waste of resources and is deployed mainly for and to maintain global class divisions in the geopolitical capitalist economy.
Immigration provides a sense of pluralism vital to ‘post’-colonial cultures, memetic contagion, and the creed of tolerance. The restriction of the flow of people in favour of a sense of nationalist citizenship may be wholly outmoded or transmogrified with the achievement of a global resource-based economy (Fresco), wherein greater interconnectivity through technological means will create new social arrangements of belonging, home-making, and identity.
Henry Willoughby's Social Justice Blog 