Government is an important part of human interactions, it is intertwined with many areas of society and culture and therefore has a social role. Government can certainly encourage and support morality. Not in the sense that it completely enforces, but it can certainly has some cautious, but not insignificant role in this area.
That's why we don't need government enforcing personal morality. Society generally does a far better job.
They are not completely voluntary, far from it. Many of the bonds are partially not chosen, such as family. Government has a role in society, it must be careful not to undermine these bonds, that is why I'm in favour of decentralised and relatively small government. But the idea it can have no moral role is simply an a priori and unsupported assumption and makes no sense. Government as an important aspect of social order and social and cultural consciousness, to be morally and culturally neutral would be to act against social and culture values and beliefs and there is no reason why encouragement of these values and beliefs should not sometimes be supported by law.I never went against these social bonds. This is because they are largely voluntary. They may influence people and attract them toward certain paths, but they differ from government force, in that they are not coercive. That's my point; these bonds make government force largely unnecessary. Right-Libertarianism is not against all authority and hierarchy, but coercion. It is a subtle distinction, but an important one.