Great topic, great challenge.

As I understand libertarianism, the 'purist' would argue that there is no need for government and that everyone should be self sufficient and that socialism creates entitlements which de-motivates society into becoming dependent rather than contributory.

I tend to agree with the principles involved but place huge emphasis on the 'that everyone should be self sufficient' bit, because we are a long way from that, long in terms of centuries or even millennia.

So I think that a sane and balanced libertarian approach is to acknowledge the ideal and understand that there is a centuries long journey to be undertaken by ourselves, our children and their children after them, for many generations to come, in order to even approach that ideal. To take the position that we should have nobody telling us what to do when for the whole, we largely don't yet know what to do for ourselves, is just plain stupid.

Any journey is taken a step at a time, and a successful journey is made of many, sometimes even thousands of successful steps. If we define a successful step as one which leaves us, collectively and individually better off, by any sane measure of 'better off', and we keep taking those steps, eventually, a generation in the future will attain that utopia.

If on the other hand we are to demand and try and force that utopia on a society which is not ready for it, we are simply going to self-destruct, as effectively as if we decided that we needed a society based on individual power, a sort of perverted vision of Darwin's theory of 'natural selection' and Spencer's theory of the 'survival of the fittest', which are linked, but neither of which were intended to imply that in human society, the biggest bully should always win and be allowed precedence and the weak should just be allowed to wither and die unless they could find the wherewithal to pull themselves up by their boot straps, a view which never the less seems to be held by many looney elements of the libertarian camp. 

They seem to forget that once they have ditched the socio-political structures of the day and have not replaced them with socio-political structures for tomorrow, they could well become islands of self-sufficiency but isolated intellectually, socially, technologically and financially, surrounded by thousands of impoverished have nothings, who under the circumstances would feel even less than nothing for the libertarians' claims for the sanctity of their lives, limbs and property to be respected.

So the challenge I see for libertarians, is to identify and walk a pragmatic path from where we are to where we need to be and to understand that a multiplicity of steps are needed to walk that path successfully and that it will take time and we need the patience of Job to undertake that journey.

To answer your question about questioning authority, yes we should, every step of the way and every minute of the day, every day. in fact, I think we need to define the term authority, or at least re-identify its source, which is that of those who cede it. as Elizabeth 1 is scripted to say in the film, Shakespeare in Love, to one of her lackeys, 'Careful how you use my name, you may wear it out'.

In a sense, for libertarianism to succeed, it needs to re-identify itself.

So what principles should Libertarians adopt?

I'll start a list and hope others add to it, although the list should be short if its content is right:

1) That respect for and compliance with the law be a cornerstone of libertarianism.

2) The sovereignty of the individual exists above that of all collectives, including that of corporates and government.

3) The sanctity of everyone's life, limb and property be respected.

4) That all exchanges should be based on quid pro quo and if not, for whatever reason, can be reversed or enforced.

5) That government's purpose, in so far as it is permitted to exist, is to serve, not to rule.

6) That the principle of 'the greater good' cannot be used to impose the will of one over another.

7) That everyone has the absolute right to do what he wishes provided in so doing he does not imping on the rights of others.

8) That no law or contract may remove or diminish an individual's rights in terms of these principles and no law that restates the above principles should be recognized. 

9) That a universally accessible judicial system exists to uphold those principles.
 
10)  Any government should be the minimum required for the orderly functioning of society.

I have a problem with the 'Libertarian Socialism' term used in another of Bev's posts. I don't believe in entitlements, which is what I believe socialism is all about but I do believe in libertarian pragmatism. I believe that a libertarian will understand that if he is the only pool of wealth in a desert of poverty, he will soon loose his wealth. In order to retain or even increase his wealth, he needs to help develop the wealth of those around him, and that he will do, not from altruism but for his own good. If he serves those about him well, particularly if that service improves their lot, he will earn their respect and support and if he is clever about it, he will also gain in wealth; financially, spiritually and socially. That is about as close to socialism that I ever want to go.