Randy Barnett is asking how libertarianism has anything to say about foreign policy at all:
...would the U.S. Army [be] acting unjustly on Libertarian grounds [if] it goes to the aid of innocent civilians in Somalia, the Sudan, or Iraq? I do not see why. If these people are indeed the victim of horrible rights violations a solder regardless of whether his uniform is American or Iraqi would be justified in going to the defense of the victim according to Libertarian first principles. So if "defensism" is a proper principle of foreign policy, it does not appear to follow from Libertarian first principle, since either going to the assistance of the innocent and not going to her assistance is an equally justified act. (This is apart, of course, from the moral duty one may have to help the innocent.)
Now, this has a certain resonance coming from somebody with Barnett's roots, and no particular allegiance to the notion of the state whatsoever. The odd part is that Barnett is somebody who has argued against capital punishment, not on the grounds that it is inherently unjust, but because he believes the state is so incompetent that it will inevitably execute innocent people.
Why then should the US government and her daisy-cutters decide who lives and who dies in Sudan or Iraq? Necessarily, wars involve huge amounts of rights violations -- namely the maiming and killing of huge numbers of innocent people. As Barnett paints it above, it's just a matter of sprinkling pixie dust over the target country and making evil disappear.
Barnett claimed earlier that "[b]ecause Libertarianism is essentially a philosophy of individual rights, I doubt it says much about what policies either individuals or collective institutions ought to pursue other than that they should not violate the rights of individuals in pursuing them." Aside from the fact again that bombing innocent people violates their rights, one of his prior blog posts paradoxically touts a recent paper he wrote that claims "Libertarians no longer argue, as they once did in the 1970s, about whether libertarianism must be grounded on moral rights or on consequences; they no longer act as though they must choose between these two moral views. In this paper, I contend that libertarians need not choose between moral rights and consequences because theirs is a political, not a moral, philosophy; one that can be shown to be compatible with various moral theories, which is one source of its appeal." So how is he arguing a few days later that libertarians can only make arguments based on rights? What about the notion of consequences?
As David Friedman has pointed out: "Few egalitarians would prefer a society where everyone had a real income of $1,000 to one where incomes ranged from $90,000 to $100,000. Few Rawlsians would choose to improve the lot of the world’s worst-off person by one dollar at the cost of massively reducing the welfare of everyone else in the world. And few libertarians, however hard-core in theory, would choose a perfectly free society of desperate poverty over one slightly less free and very much wealthier."
If he allows for consequences to matter, the assumption Barnett must make is that on balance, the population of a target state will necessarily end up better off after we're done working our magic. His position would be incoherent otherwise -- (Americans are worse off, because the government has taken our blood and treasure to try to defend the rights of people in another country, but now they're worse off too.) So he can't really get away from the notion of consequences at all. Consequences matter, too, and I think the historical record is out on whether frivolous US wars have netted good consequences.
So aside from the fact that elective wars cause the US government (and possibly by extension, the US electorate) to become massive rights-violators, we would have to be pretty sure that each intervention makes Americans and our targets better off, or at least a majority of the population on the whole.
But even if the thing comes out okay, it's never going to be pareto-optimal. And then how is that not the oppression of a minority by a majority? Gene asks:
Does it violate libertarian principle for the U.S. government to wrest scores of billions of dollars from the American taxpayer (possibly as much as $3,000 per American family) in order to address rights violations committed half a world away against people not under its protection?
I'd say it does. I have a right to come to the defense of others. I do not have the right to steal Randy Barnett's car in order to do so.
Right. I could go on and on, but I'm frankly a little puzzled why we're having this debate at all.