Jon Mandle of Crooked Timber reports at length on a Kennedy School Conference on global equality here.
Much of it is the kind of thing that drove me nuts about political theory in the analytical tradition. But I think Larry Summers, who you may recall was recently drummed out as President of Harvard University for musing that chicks may just be naturally bad at math,* asked a big question.
On the one hand, no democracy can possibly equate the well-being of its own people with the well being of foreigners. On the other hand, it equally can't say that foreigners have no moral claims on it at all. So what's the ratio: should the Canadian government value a Canadian life at two Ethiopian lives or 100?
His interlocutor suggested that this was exactly the kind of question that only nacho boys ask, and to please stop.
I think the problem here is that Summers, as an economist, has the utilitarian tendency to equate acts and omissions. His audience, as fuzzy-minded one worlders, share this tendency. But the problem disappears if we reinstate the distinction and presume people have certain natural rights to be left alone if they haven't done anything to us.
With respect to those natural rights not to be aggressed against, foreigners and Canadians are equal as far as the Canadian government goes. In fact, the Canadian government certainly has the right to tax Canadians, and possibly to conscript them, but doesn't possess that right in relation to anyone else. So there is total equality in relation to this right.
On the other hand, while the Canadian government owes non-Canadians equal duties of non-interference, and equal duties to abide by its solemn commitments, it owes no fiduciary duties to non-Canadians. It isn't just that it owes a lesser fiduciary duty to Ethiopians, but it owes no fiduciary duty at all. There is no (formal) inequality here, because the Ethiopian government similarly owes no fiduciary duties to Canadians.
Naturally, a formal equality is consistent with (and, in fact, implies) a material inequality. But we can't dispense with that material inequality by taking on a "duty to protect" Ehtiopinas. On the contrary, when we do that we, for better or for worse, take on an imperial role, and therefore turn what was formerly a material inequality back into a formal one.
*Actually, he suggested that the variance in innate mathematical capacity might be greater for XY types than for XX types, even if the mean is the same. Not that that nuance helped him.