Libertarians have always acknowledged that emergencies -- severe extraordinary conditions of limited duration -- can justify actions that would be unacceptable under normal circumstances. This doesn't mean that all the rights-based rules disappear, only that some measures are deemed permissible that otherwise would be beyond the pale. Danger, however, lurks in this principle, requiring eternal vigilance. For example, if someone collapses unconscious in the street, you may do things intended to help him without his consent. This does not justify a general policy of paternalism. Another common...