Finally, for safe vaccines to prevent the most communicable and dangerous illnesses, vaccine mandates can fit within even a very narrow view of government’s role.

Libertarian Ron Bailey put it well in Reason magazine. Citing Oliver Wendell Holmes’ famous line that “The right to swing my fist ends where the other man’s nose begins.” Bailey argues aptly: “Being intentionally unvaccinated against highly contagious diseases is, to carry Holmes’ analogy a bit further, like walking down a street randomly swinging your fists without warning. You may not hit an innocent bystander, but you’ve substantially increased the chances that you will.”

Measles are highly contagious and can be spread through the air. No parent can plausibly promise to keep their unvaccinated kid from getting or spreading measles. As long as you accept government’s role of protecting the innocent from violence, it’s easy to see where government has a role in requiring safe and effective vaccines for highly communicable diseases.

This argument doesn’t apply to vaccines for less easily communicable diseases, such as the sexually transmitted human papillomavirus, or HPV.