The usual economic use of the term "externality" refers to a cost (or
benefit) imposed on someone who is not part of the transaction or
does not have a choice in the matter.
When chattel slavery was legal, some labor cost was an externality:
the loss of enjoyment from being required to work 16 hours a day
would be imposed on the slaves who had no choice, not on the
slaveowners who make the decision.
Today, if an employer tries to impose the same work regimen, he will
pay his laborers dearly and still see many of them depart for more
pleasant positions elsewhere. Labor is no longer an externality.
In regard to a gun, benefits received by the gun buyers are not
externalities. Neither are costs imposed upon criminals who attempt
to rob gun buyers. The benefit to PEOPLE IN GENERAL from having
those criminals removed from circulation, is an externality; and
almost everyone benefits in this way. The cost to PEOPLE IN GENERAL
from gun accidents is an externality; but in most cases this cost is
born by the gun buyers, *not* by people in general.
> There are myriad resource costs in producing a firearm. There : is
> one benefit -- the firearm itself. Any remote benefit not :
> balanced against costs in the decision to manufacture is external. :
> Self-defense falls into this category.
The benefit of self-defense accrues to people who willingly take part
in the gun buying transaction and who willingly pay a price for that
benefit. About as far from an externality as any effect can be.
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