“Liberty isn’t the only value” he said, while pointing his gun at my head. - geoif
My response to the question "is liberty the only value that matters for libertarians?" would be the following: no, but it is clearly the most important one, by which I mean that it requires unqualified respect and constitutes a necessary precondition for the realization of any other value.
There can be no justice without liberty, since justice is equality before the (natural) law, and allowing anyone to enjoy his natural rights while violating those of others is the paradigm of unequal treatment. There can be no charity without liberty, since charity involves voluntarily giving away one's own goods, not forcibly extracting them from others and taking a commission for it. There can be no gratitude without liberty, since the feeling of coercive entitlement to someone else's wealth is the very opposite of gratitude. And so on for other values.
Every good deed requires voluntary intention and respect for the voluntary intentions of others. Every act of coercion destroys the moral worth of one's intentions by trampling over the intentions of others, by their instrumental and exploitative treatment, which necessarily constitutes the dehumanization of their owners, the essential features of human beings being free will, purposiveness and self-ownership.
Putting things this way, libertarianism seems to me not only not to exclude values other than liberty, but also - in contrast to every coercive doctrine - to give them the proper respect they deserve - that is, not treat them as excuses for one's envy, lust of power or any other vice in virtue's clothing.