I've got a setting where a small group (10 million) of survivors rebuilt semi viable civilization on a distant, hospitable planet. They used superscience teleportation, actually their technology is not much better than early XXIst century.
They've lost contact with other human groups for almost 100 years. According to their knowledge at least few other groups should have survived. No idea about their intent. No idea about their strength. No idea whether there would be any contact. Actually teleportation "technology" allows even small group to open their gate.
Society on its own is quite peaceful, low-crime, prudent, risk averse etc. What would be the realistic military level that they keep anyway?
I know that there is a hint of opinion based, so I'd like more to put some reasonable brackets, between which such society should stay under normal conditions.
I see that there is a risk of some subjectivity, not mentioning that real life military spending fluctuate based on gov in power and mood of public opinion. So instead I ask what are realistic lower and upper bounds, that such society should stay within? My types:
some police special unit (they should have it anyway)
air control / weather radars, that would also be able to detect intruder aircraft
surveilance system to detect home grown potential terrorist and organized crime, what could also have a chance to detect some spies
some armored cars to be able to overwhelm a person with hunting rifle
stockpiled reserves in case of natural disaster
military strong enough to be able to make a coup d'etat (so their military should be a bit defanged), so very high civilian supervision even if it means reduced efficiency
military would be a tempting target for budget cuts so it's unlikely that they would spend more than a contemporary social democracies
small society means lack of economics of scale, so huge part of military equipment would have to be off the shelf civilian equipment
Any more ideas where I should put lower and upper bands? I specially think to what extend they should be able to make themsleves not worthy target for band of low tech but numerous nomads, or high tech mercenaries that read too much about Hernan Cortes? Or maybe its 100% based on their opinion, and the only thing to make it realistic is to show that such opinion changes every few elections?