I think the problem specifically as it relates to the military is that the Federal government can do whatever they want with soldiers *except* for violate certain enumerated Constitutional rights. And a right to bodily autonomy has never been recognized, whether that is supposed to be implicit in the Constitution or not. In other words, if they are trying to force the vax on civilians, you can argue it's outside their purview (although apparently the Supreme Court has ruled it's totes cool.) With respect to soldiers, the scope of the Federal government is much greater. For instance, consider freedom of movement. Civilians basically have that right. Soldiers don't. The government can restrict their travel even in their off time. I think that the Constitution should contain a right to bodily autonomy. I don't know that it does. You could argue analogous things in the 4th amendment, but it seems actually unanticipated by the Bill of Rights. I don't think they anticipated the government trying to stick something in you. They do seem to have anticipated the government trying to extract something from your person, hence the prohibition against unreasonable search and seizure.