People always trying to turn everything into a black or white issue, along with negativity.
As a libertarian you should still favor a strong federal military. Where does the money come to pay for that? It comes from you and me. You still do not get to keep everything that you earn.
As a libertarian you should favor the right of the individual over the state. That means not creating laws that deny others their rights - be that owning assault weapons, having an abortion, etc.