Just who is 'the enemy'? This is something we each have to answer for ourselves. Are your preparations geared toward social/economic collapse & the mayhem that would accompany it?

Are you planning to fight an out of control tyrantical government that has slipped it's constitutional restraints?

Do you expect to defend against a foriegn invasion?

All of the above scenarios pose unique challenges.

S/E collapse means the infastructure is gone. Wide areas will be simply impassable as warlords rise up to control them. No more deliveries to the grocery stores, no more running to wallyworld for the little stuff. If you don't have it going in don't expect to have it at all. Disease, starvation & chaos will drive otherwise good neighbors to unspeakable acts as they struggle to survive. Military units can not be expected to sit quietly in garrisons munching on a limited supply of MREs. They will have access to state of art hardware & the training to use it. Expect them to go rogue. They may well be some of the warlords

Out of control government? We're almost there. The means of production & distribution would still be place. But so would the power of the state security apparatus control it & to hunt down "terrorists" "criminals" or whatever name they hang around your neck. You can bet that your families would be considered fair game (ask Randy Weaver) & would have to be evacuated to safe retreat locations. Don't count on alot of help from 'our' military, they're paid by the tyrants & few will bite the hand that feeds them.

Invasion? Already happening. They just don't wear uniforms or drive tanks. YET. At least this one would allow us to function as auxiluary or guerrilla forces. Families could be sent to safer locations though in an era of NBC weapons that may be a non sequiter