Some, hardly a majority, truly feel that they will be fighting off tanks with rifles any day now.

Yes, and these people belong in asylum. They should be prevented from having access to paring kniives, never mind firearms.

Usually these people have no idea of what a truly horrible business war is...

Not surprising, since the evidently don't know what reality is, either.

instilled a paranoia in many in the US that, I think, continues to this day. It isn't helped by films like "Red Dawn"

Nor is it helped by craven, mostly Republican, politicians who constantly rave on about rapist Mexicans, killer Muslims, "Wars on Christianity", terrorists of every stripe and nationality out to "get" the U.S., rampaging, criminal Blacks folks, jack-booted thugs coming to "take away our guns" and all the other shibboleths that are the daily output of outfits like Fux "News"[sic].

See also Hofstadter: "The Paranoid Style in American Politics" 1964.