Historically most ancient or medieval wars were fought by professional soldiers.

Here is a Wikipedia quote

"The persistent old belief that peasants and small farmers gathered to form a national army or fyrd is a strange delusion dreamt up by antiquarians in the late eighteenth or early nineteenth centuries to justify universal military conscription"

I support Rothbard's view on the issue: https://www.youtube.com/watch?v=i3TY5OhUJhw