In order to justify SCDJ, Miller offers three normative reasons: the metric problem, the dynamic problem and the lack of global institutions of citizenship. First, the metric problem is derived from the fact that owing to global cultural diversity;
common normative understanding is too thin for all human beings to reach the same valuation of natural resources and for the content of opportunity sets to be equalised globally. Miller examines two categories of the distributive egalitarian proposals: (1) the equalisation of the access to natural resources and (2) the equalisation of
opportunity sets. Firstly, Hillel Steiner’s ‘global fund’ proposes to tax the resource-rich nation-states according to the aggregate value of their natural resource holdings and redistribute the revenue among the resource-poor nation-states. Contra Steiner,
64 Miller argues that there are three factors accounted for entirely by human decisions and behaviours rather than nature itself: (1) the set of rules of conditions under which the natural sites are held, (2) the abilities and the preferences of the people who might use the property and consume what is produced there and (3) the impact of the surrounding neighbourhood on the property value of the natural site. That is to say, the aggregate value of a particular nation-state’s natural resources depends on the human decisions and behaviours that legislate certain sets of rules that regulate the uses of natural sites within its jurisdiction. It is also influenced by the local culture that shapes consumer preferences and the composition of the labour market in certain ways. Equally, the characteristics of the surrounding neighbourhood can raise as well as lower the property value of natural sites significantly (Miller, 2007, p.
60). Even though these factors include various aspects of human decisions and behaviours—political decisions, consumer preferences and the development of employable skill sets, et cetera—they all depend on a shared normative
understanding about the value of certain natural resources. Indeed, as Miller argues,
Steiner’s proposal to tax nations according to the aggregated property values of the sites they contain…appears arbitrary…Nations contribute to the creation of their own aggregate property values in at least the three ways we have just traced. So if they are taxed on that basis, they are to a considerable extent being taxed according to the values they adhere to collectively and the choices they have made (Miller, 2007, p. 60-1).
In other words, in the face of multiple normative understandings about certain natural sites within nation-states, it will be very difficult for human beings to come to a single, non-arbitrary tax scheme that uniformly extracts revenue from each nation-state.
65 Secondly, Moellendorf claims, ‘if equality of opportunity were realised, a child growing up in rural Mozambique would be statistically as likely as the child of a senior executive at a Swiss bank to reach the position of the latter’s parent’
(Moellendorf, 2002, p. 49; cited by Miller, 2007, p. 63). In order to realise this distributive egalitarian vision and equalise opportunity sets globally, Miller argues that some kind of metric is needed to decide whether two opportunity sets are at least equivalent. However, this is where the cosmopolitan principles of global distributive justice encounter an obstacle. Since people rely on a common normative
understanding in order to flesh out the general ideal of equal opportunity in more substantive terms—that is, ‘a number of specific types of resource and opportunity are singled out as significant, and these are not regarded as substitutable’—at the domestic level, greater cultural diversity at the global level renders this type of collective decision unattainable (Miller, 2007, p. 66).
Second, the dynamic problem is derived from the idea that the people within nation-states should take responsibility for their collective decisions in the past which have differential distributive outcomes today. Miller illustrates this idea with a
hypothetical case wherein two societies make different collective decisions to employ natural resources in respectively consumerist and conservationist ways, and end up with unequal distributive outcomes. In this case, he thinks that extensive redistributive measures to restore the substantive equality between these two
societies would ‘leave very little incentive for states and their citizens to behave in a responsible way’ and in extreme cases may even compromise the political self-determination of these societies (Miller, 2007, p. 70- 4). Third, the lack of global institutions of citizenship marks the global level off as a different distributive context than the nation-state, insofar as the ethical demands of distributive justice are
66 grounded in the social ideal of equal relations among citizens. As discussed in
Chapter 1, both basic needs satisfaction and substantive inequality regulation are justified on the basis of their contribution to human beings’ equal status under the shared political institutions of the administrative state. Therefore, Miller argues that a nation-state is a different distributive context to the global sphere, in the sense that it consists of four characteristics all at the same time. That is to say; a nation-state places individuals under shared legal coercion, gives them involuntary membership, enables them to pursue reciprocal cooperation and supplies them with a collective identity (Miller, 2013, p. 151- 61). Insofar as human relationships at the global level do not bear these four characteristics, at least not to the same extent as within nation-states, the regulation of substantive inequality is not morally relevant.