Dave,
Of course you're right, advocacy of limited government is an ideology. Some people might even call this ideology "libertarianism," but I think our philosophy of non-aggression logically encompasses some types of anarchy as well as it does limited government.
I'm not exactly sure what you wished to communicate in pointing out that this, too, is an ideology. Of course it's "utopian," in the sense that it's a long way from where we are now. Abolishing slavery was once considered equally utopian and contrary to human nature. Clearly limited government is not utopian in the sense of being impossible -- we know it is possible. It *may* be utopian to think that such a system can be made stable for long periods of time (though I personally think such stability is achievable). On the other hand, it may be equally utopian to believe in a long-enduring welfare state.
In general terms, you could say there are sort of four basic options of how much government to have (with all shades of grey in between, of course):
(1) authoritarianism
(2) welfare state
(3) limited government
(4) anarchy
Of course laying it out like this would appear to give some credence to anarchy as being the most pure, or farthest from authoritarianism. But we would be remiss not to expand this list to consider the other historical category of "no government" beside the rarely-achieved one that anarchist libertarians theorize about. Thus we have three basic categories of government and two basic categories of "no government":
(1) (govt.) authoritarianism
(2) (govt.) welfare state
(3) (govt.) limited government
(4) (no govt.) civilized anarchy (healthy free market competition, generally enforceable contracts, etc.)
(5) (no govt.) uncivilized anarchy (law of the jungle, might makes right, etc.)
Now obviously a society would not always move sequentially backward or forward from one category to the next, but I'd guess it that sudden transitions from, say, anarchy to a welfare state, or limited government to authoritarianism are pretty rare. I can also envision this list as a circle that wraps around at the ends -- i.e. it's much easier to move from uncivilized anarchy back to authoritarianism or vice-versa than to move from either of these forms to limited government.
Now it's also true, as you say, that limited government has rarely been achieved, but if anything this is even more true for libertarian-style anarchy.
We know that in comparisons between societies with greater or lesser amounts of government, the evidence is very strong that less government works better. It's theoretically possible that no government could work even better, but except for medieval Iceland there seem to be no examples of a stable anarchy (i.e. one persisting over time in relatively ordinary conditions as opposed to unusual and unsustainable circumstance such as bands of pirates or the Wild West frontier) in history, and I'm not sure how much is really known about medieval Iceland (admittedly, I haven't read the literature).
In short, we don't know whether it's easier to keep limited government from sliding into a welfare state, or to keep civilized anarchy from sliding into uncivilized anarchy. It does seem to me however that the distance between uncivilized anarchy and authoritarianism would tend to be much more quickly bridged than the distance between a welfare state and authoritarianism.
Although we don't know this, we do know a lot more about how limited government has functioned, and about the processes by which limited governments have eroded into welfare statism, than we do about how civilized anarchy functions and how it may erode into uncivilized anarchy, I feel the much safer bet at this point is to try to construct a stable and enduring system of limited government than to try to construct a stable and enduring civilized anarchy.
I am quite curious at this point to learn more about the Icelandic experience. Perhaps someone here can speak to how that anarchic society collapsed, and what followed it?
Yours in liberty,
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