Isn't it just a little silly to compare any one individual thinking about home defense with one gun to the Powell Doctrine?
Doc is right.
Plus, even though where I live is pretty home-defense friendly, the news media certainly present the use of AKs (and such) in home-defense situations (which does happen from time to time here) as scandalously as possible. Being that DAs are political animals, such coverage could very well have some effect on how they react in reviewing a shooting. As a former prosecutor, I can assure you that many police officers and prosecutors would be more inclined to look askance at a person using such a gun for home defense - even here in the hairy-chested West.
Just something to consider - everyone should decide what's right for him/her and do that. And you might consider easing back on the throttle when comparing your home defense plan to superpower warfare doctrine.
Just a friendly little hint from a former prosecutor . . .