I don't see you out on the street manning the barricades.
It would seem that the system by which he maintained them was that he assigned to each a region of which the inhabitants were responsible for its manning and its sustentation.
As soon as I started firing, the guy manning the laser stopped firing and aimed somewhere else.
Through the eyes of your character, Tommy Conlin, you forcibly attempt to make your way up from the ocean, manning a gunship in the process as you take down enemies from all directions.
Peyton Manning plays like this every game.