Who is responsible?

I, for the most part, agree with the economic theories of the Austrian School, as propounded by Mises, Rothbard and Hayek, among others. A great source for this economic thought is found at www.mises.org.  Anyway, recently I was reading a post discussing the place of government controls over the consumption of alcohol.  I commented on this post with something about the government's responsibility to protect the innocent.  Another commentator balked at this and called my comment absurd.
This got me thinking.  Is it the responsibility of the state or federal government to protect the innocent or is it merely to punish the guilty? Should the government step in and protect people from their own foolishness?  What if that foolishness has serious adverse effects upon extended family or the community at large?  Who then decides what is adverse? Should we leave protection up to private organizations? If we look at a strongly patriarchal society, husbands and fathers protect their women and children.  But what about a seriously liberal society when the men have become effeminate and self centered?  I really hesitate to give the federal government any power other than the authority of representation.  But I also cannot see just leaving the weak to fend for themselves.
We could talk about the actions and responsibilities of individuals but one person can only do so much.  One person can only expend so much time and money, regardless of desire to do much more.  There must be something here about the strong protecting the weak. 
Ultimately this is about love for neighbor.  What are we responsible to do in order to be obedient to this command?