What turns on this from a moral point of view is the level of moral concern that members of this kind of union owe each other. Are their obligations limited to the domain of "concern" that gives rise to some obligations of charity? Or are they closely enough interconnected that they are subject to the demands of justice towards each other? If the latter then the difference principle applies to them when inequalities of life circumstances are apparent. If the former then only weaker principles of assistance apply.
For van Parijs this question is particularly acute in the case of Belgium, which was even then subject to fissional pressures along linguistic-cultural lines between Flemings and Walloons.
Van Parijs and Rawls exchanged several careful and thoughtful letters on these issues in 1998, and these letters were published in their entirety in Revue de philosophie économique in 2003 (link).
The disagreements between van Parijs and Rawls are very interesting to follow in detail. There is one aspect of the exchange that is particularly intriguing on the subject of Rawls's own assessment of modern capitalism. The passage is worth quoting. Here is an excerpt from Rawls's letter:
One question the Europeans should ask themselves, if I may hazard a suggestion, is how far–reaching they want their union to be. It seems to me that much would be lost if the European union became a federal union like the United States. Here there is a common language of political discourse and a ready willingness to move from one state to another. Isn't there a conflict between a large free and open market comprising all of Europe and the individual nation-states, each with its separate political and social institutions, historical memories, and forms and traditions of social policy. Surely these are great value to the citizens of these countries and give meaning to their life. The large open market including all of Europe is aim of the large banks and the capitalist business class whose main goal is simply larger profit. The idea of economic growth, onwards and upwards, with no specific end in sight, fits this class perfectly. If they speak about distribution, it is [al]most always in terms of trickle down. The long–term result of this — which we already have in the United States — is a civil society awash in a meaningless consumerism of some kind. I can't believe that that is what you want.Several aspects of this passage are noteworthy. The first is a tentative skepticism about the goal of creating a European community in a strong sense -- a polity in which individuals have strong obligations to all other citizens within the full scope of the expanded boundaries. Rawls seems to equate this goal with the idea of creating a somewhat homogeneous and pervasive European culture, replacing German, French, or Italian national cultures. And he offers the idea that the traditions, affinities, and loyalties associated with national identities are important aspects of an individual's pride and satisfaction with his/her life.
So you see that I am not happy about globalization as the banks and business class are pushing it. I accept Mill's idea of the stationary state as described by him in Bk. IV, Ch. 6 of his Principles of Political Economy (1848). (I am adding a footnote in §15 to say this, in case the reader hadn't noticed it). I am under no illusion that its time will ever come – certainly not soon – but it is possible, and hence it has a place in what I call the idea of realistic utopia.
What is surprising about these views is that Rawls seems to overlook the polyglot, poly-cultural character of the United States and Canada themselves. Both North American countries seem to have created some remarkable solutions to the problem of "unity with difference." It is possible to be a committed United States citizen but also a Chicago Polish patriot, a Los Angeles Muslim, or a Mississippi African American. Each of these is a separate community with its own traditions and values. But each can also embody an overlay of civic culture that makes them all Americans. It certainly doesn't seem impossible to imagine that Spaniards will develop a more complex identity, as both Spaniard and European. So Rawls's apparent concerns about homogenization and loss of collective meaning seem ill founded.
Even more interesting, though, are his several comments about globalization and capitalism. As we observed in a post about the property-owning democracy (link), Rawls has already expressed the idea that capitalism has a hard time living up to the principles of justice. Here he goes a step further and reveals a significant mistrust of the value system created by capitalism. He refers to the world the "bankers and capitalists" want to create -- one based on acquisitiveness and the pursuit of profit -- and he clearly expresses his opinion that this is incompatible with a truly human life.
The goal of perpetual growth expresses this ideology, and Rawls reveals his skepticism about this idea as well. He offers the opinion that the pursuit of growth by this class is no more than the pursuit of greater wealth and more meaningless consumption. And he clearly believes this is a dead-end. Instead, he endorses J. S. Mill's idea of a steady-state (link). (Interestingly, this position lines up well with current thinking of environmentalists; for example, James Gustave Speth and The Bridge at the Edge of the World: Capitalism, the Environment, and Crossing from Crisis to Sustainability (link).)
Here Rawls seems to express a cultural critique of capitalism: the idea that the driving values of a market society induce a social psychology of consumerism that overrides the individual's ability to construct a thoughtful life plan of his/her own.
Finally, Rawls criticizes the neo-liberal dogmas about distribution of income that had dominated public discourse in the U.S. almost since the publication of A Theory of Justice: the theory of trickle-down economics. That theory holds that everyone will gain when businesses make more profits. And, of course, the data on income distribution in the U.S. since 1980 has flatly refuted that theory (link).
(Van Parijs' most recent book, Linguistic Justice for Europe and for the World (Oxford Political Theory), will be published in October. It is highly relevant to this debate with Rawls.)