If you want ordinary people to make your society occupation-proof, you have to teach them to kill well before they need to do so.
and
In Finland, adolescent males report for a short and intense period of military training, followed by shorter refreshers for most of their adult life. The training is not, as in the Israeli model, a few years of dedicated service. Nor does it emphasize military discipline, such as keeping one’s bunk tidy and shoes polished, or the Prussian-style transformation of citizen-recruit into fighting machine. Instead, it prepares civilians to be ready to join their unit and harass and kill invaders