One fights the enemies of the state, the other serves and protects the people.

I sometimes quote this to people

There’s a reason you separate military and the police.
One fights the enemies of the state, the other serves and protects the people.
When the military becomes both, then the enemies of the state tend to become the people.
– Commander William Adama, Battlestar Galactica (imdb)

painfully relevant, considering there’s military personnel on duty in our cities these days.