There is a problem with the type of ideal you describe.

If (as previous comments suggest) libertarian ideal is something that only works in its entirety, then introducing a 'libertarian law' outside of a libertarian system is damaging. It may be a step towards the completion of you ideal in a very general way, but if it doesn't get you closer to it, doesn't improve the intermediary state etc. etc. , then it's not a good law.