Here's a definition from The Pocket Dictionary of Apologetics & Philosophy:
libertarianism (political). In political philosophy, the view that individual human freedom is a primary value and that government restrictions on that freedom should be limited to what is necessary for the maintenance of a society that is conducive to freedom. Thus libertarianism offers a justification of state power over against anarchism, but it holds that there is moral justification only for a minimal state sufficient to defend citizens against attack and protect against crime.Does the Bible offer any support for this kind of libertarianism? I believe that it does.
Do not contend with a man for no reason, when he has done you no harm.
If possible, so far as it depends on you, live peaceably with all.
For rulers are not a terror to good conduct, but to bad. Would you have no fear of the one who is in authority? Then do what is good, and you will receive his approval, for he is God’s servant for your good. But if you do wrong, be afraid, for he does not bear the sword in vain. For he is the servant of God, an avenger who carries out God’s wrath on the wrongdoer.