I periodically flirt with isolationism, or if you prefer, "non-intervention". Like most libertarians, I'm attracted to "high concept" political philosophy: simple rules that can be stated in a sentence or less. No arguments about causus belli, blowback, or ultimately unknowable political ramifications; just a simple "yes or no" test. Did a foreign army invade the United States? For "Yes", press one; for "No", press two, and go back to arguing about what should replace child welfare laws in the coming anarcho-capitalist society.

Besides, all the foreigners hate having us there. Why not leave, and see if absence makes the heart grow fonder? (I suspect that many nations which have come, over long decades, to regard regional peace as some sort of natural law, will get a rather nasty surprise. This might make our influence look, in retrospect, rather appealing.)

But anyone who thinks at all seriously about libertarianism will, fairly early on, be faced with a very high hurdle. There are a handful of wars in which American intervention unambiguously halted gross abuses of human liberty. World War II is one, though many end up going around, rather than over . . . arguing that the Nazis were the direct result of American intervention in World War I; or that it was justified because Japan attacked us1; or that Russia and Britain would have defeated Hitler anyway2. The American Civil War, however, is by far the highest leap; and the hardest to dodge.

In theory, every state has the right to secede, and the stated Federal rationale for the Civil War--preserving the union--was the vilest tyranny. In practice, chattel slavery was a barbarism even viler.

And so we killed 20-30% of the Confederate Army, not a few of our own, and uncounted numbers of civilians. That's not counting the wounded, who probably outnumbered the dead. All we managed to achieve, at this horrendous cost, was a corrupt and brutal occupation, followed by the "freedom" of Jim Crow, sharecropping, and "separate but equal". And it was worth it. The good guys won. We didn't do everything we wanted to, or even everything we could have, or should have. Jim Crow was putrid. But it was nonetheless so much better than slavery that it was worth the horrendous cost--in my opinion, and that of almost everyone in the world.

Hard-core non-interventionist policy doesn't have a very good model for this--at least not one that I've seen. Either the states didn't have a right to secede; or we had right to invade a sovereign nation and occupy them in order to end slavery; or you have to leap the hurdle and say "Yup, we should have left the South alone". Some libertarians do say this, and not because they're racists; the price of intellectual consistency is embracing occasional bad results. I think this is wrong, for all sorts of reasons, but I do understand the allure of consistency. Because if you don't take their position, then suddenly you no longer have a high concept policy, full of hard-and-fast rules that could be applied by any literate twelve-year old. Suddenly you're mired in arguments about which practices merit intervention, and which are merely offensive, and how much of our own national interest we are obliged to sacrifice in these sorts of humanitarian efforts.

Thus non-interventionists fairly often end up in debates over what would have happened if we'd just let the Confederacy go. Jim Henley's post on the topic is interesting and very thoughtful, but like most of these arguments, it seems to me too willing to embrace the comfortable belief that intervention never achieves any substantial positive effect. I am very suspicious of any model which validates someone's policy preferences by proving that there are absolutely no tradeoffs. This is what drives me crazy about the supply-siders: rather than facing the implications of what they advocate, they resort to fairy-tale scenarios in which all the problems magically disappear. One occasionally stumbles across Pareto improvements in the policy world, but they are rarer than hens' teeth.

It is true that slavery was on decline in the developed west in the late 19th century, but that story, at least as I understand it, is rather complicated. Britain and Spain abolished slavery in far-off colonies; it was not economically important to most voters. The numbers involved were comparatively small, relative to the British Empire's population; something less than a million, compared to 4 million slaves in the American South. In Britain, slavery's economic importance was declining as industrial production replaced agricultural commodity trade as the economy's main engine of growth. In Brazil, too, it was a relatively weak institution, declining due to competition from foreign labor. In Russia, the serfs were not quite equivalent to chattel slaves, and in any case, there too, they were freed under the aegis of an absolute monarch who wanted to modernize the economy.

But in the American South, slavery was still a vital and thriving economic institution at the time of the Civil War, as economic historian Robert Fogel has shown in his brilliant Time on the Cross. Would it have been eliminated quickly? Even if it had declined economically, would the Confederacy have gotten rid of an institution that was central to its foundation?

I think it's rather more plausible to believe that a breaking away would have strengthened the institution. For one thing, an independent Confederacy could have relegalized the slave trade, outlawed since 1808. (This might well have had the side effect of extending slavery elsewhere, as Confederate-supported slave trade brought new sources of cheap supply to areas where immigrants were making slavery uncompetitive.) For another, I think Jim is massively overestimating the number of slaves who escaped; estimates I've seen put the number of runaways at about 1,200 a year, out of a population of 4 million. That's even with the basically non-existent enforcement of the Fugitive Slave Act. Escaping turns out to be very difficult when you need a travel permit to be anywhere more than a few miles from your house, as any Russian defector can attest.

It's hard to imagine any scenario in which more than a handful of blacks ended up in the north; the slaves mostly didn't escape, and if they'd been free, it seems doubtful that we would have allowed them to immigrate in massive numbers. The best case scenario seems to be 4 million blacks nominally free but subject to a more vicious version of Jim Crow, unmoderated by the safety valve of northern migration.

That slavery would have ended, eventually, is probably true. But how "eventually"? Obviously, if slavery would have ended in 1862, then our invasion was counterproductive; on the other hand, if they had just managed to get rid of it last year, I imagine that most people, probably even Mr Henley, would vote in favor of a retrospective invasion. But how about 1900--would it have been better to leave another two generations of blacks under the lash? What about 1920? 1950? How many generations of suffering are enough to justify intervention? No evil lasts forever, after all; if nothing else, eventually the sun will go nova and incinerate us all with magnificent even-handedness. How long before that happens are we entitled, or even obligated, to say "enough!"--and make it stick?




1Er, yes, in response to naval activity in their sphere of influence, thousands of miles from the continental US

2Really? Without our meddling, decidedly interventionist Lend-Lease and merchant shipping programs? More to the point, would they have liberated the camps before Hitler finished his Final Solution?

3Much harder to escape your owner than to legally board a train.

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