AdvanceChanged this version
The Young can Serve
How old does a boy have to be before he is a man? How old must he be before he can die for his country? Some rulers are squeamish; We, on the other hand, are an equal opportunity butcher.
Advance tree
The game files don’t say where this goes: it has no requires, so the game places it in the 
Revolutions tree itself.
Modifiers
Definitionin_game/common/advances/4_choices_mil.txt:392
394icon = regimental_system
395for = mil