The relationship between liberty and morality can be described briefly in the following manner: morality without liberty is impossible, and liberty without morality is very fragile. There can be no morality without liberty, since violating someone's liberty bespeaks a fundamental lack of respect for another person's moral agency. But in all likelihood there can also be no lasting liberty without morality, since broadly understood immorality - which manifests itself not in violating another's liberty, but in what is typically called license or debauchery - bespeaks a lack of respect for one's own moral agency. And this, in turn, leads naturally, even if not inevitably, to a loss of respect for the moral agency of others, as well as to a general erosion of respect for the value of free action.
In other words, an enslaved society will always be demoralized, but a demoralized society will always run a higher risk of falling into enslavement, both physical and mental. Perhaps this is the best illustration of the fact that understanding liberty as an end in itself cannot be separated from understanding it as a means to other ends in themselves - ends that are equally valuable, equally demanding, and equally significant in the context of fulfilling one's personal potential.