In 2008, there were 14,137 homicides in the US (source), of which 9,484 involved a firearm (source). If we assume (very generously) that none of these would have happened if there were no civilian firearms, we'd save 9,484 lives.
In 2008 the value of a life was £6.9 million (source), so those deaths cost $65,400 million.
Banning guns wouldn't (supposedly) just save those though; it'd also save lives in future years. As this functions like an investment, we'll discount it by 10% (long run stock market return), and get a present value of $654,000 million.
There around 270 million civilian guns in the US (source).
In 2008 4,498,944 guns were produced (source), and industry revenue was $9.4 billion (source), for an average price of $2,089. (possibly a slightly over-estimate if military/police weapons cost more, but might also get bulk discounts).
So the total price of the US civilian gun stock (2008) is $564,000 million.
Now the contentious bit. If the ban magically destroyed all these guns, we'd lose not only their price but also their consumer surplus. Let us utter handwave and say the surplus is the same as the price. So we'd lose $1,128,000 million.
Therefore the net present value of a ban is $654,000 million - $1,128,000 million = negative $474000 million.
Contentious assumptions made:
Focusing on the money makes a lot of sense to me. If we are honest with ourselves about the monetary incentives at work here, the whole discussion gets more realistic.
I'm also reminded of the historical conversation having to do with the 13th amendment: In one swoop of the pen, a vast sum of money was wiped off the books, the value of all that property which was now nullified.
I don't have a lot of ideas on how to make guns less profitable- unlike drugs, their high value has less to do with their legal status. But I don't think the gun lobby has got the nation's best interests in mind.
I don't know how to keep this topic away from http://lesswrong.com/lw/gw/politics_is_the_mindkiller/ , so I'm just going to exhort everyone to try to keep this about rationality and not about politics as usual. I myself have strong opinions here, which I'm deliberately squelching.
So I got to thinking about the issue of gun control in the wake of a recent school shooting in the US, specifically from the POV of minimizing presumed-innocents getting randomly shot. Please limit discussion to that *specific* issue, or we'll be here all year.
My question is not so much "Is strict gun control or lots of guns better for us [in the sole context of minimizing presumed-innocents getting randomly shot]?", although I'm certainly interested in knowing the answer to that, but I think if that was answerable we as a culture wouldn't still be arguing about it.
Let's try a different question, though: how would we know?
That is, what non-magical statistical evidence could someone give that would actually settle the question reasonably well (let's say, at about the same level as "smoking causes cancer", or so)?
As a first pass I looked at http://en.wikipedia.org/wiki/List_of_countries_by_intentional_homicide_rate and http://en.wikipedia.org/wiki/List_of_countries_by_firearm-related_death_rate and I noted that the US, which is famously kind of all about the guns, has significantly higher rates than other first-world countries. I had gone into this with a deliberate desire to win, in the less wrong sense, so I accepted that this strongly speaks against my personal beliefs (my default stance is that all teachers should have concealed carry permits and mandatory shooting range time requirements), and was about to update (well, utterly obliterate) those beliefs, when I went "Now, hold on. In the context of first world countries, the US has relatively lax gun control, and we seem to rather enjoy killing each other. How do I know those are causally related, though? Is it not just as likely that, for example, we have all the homicidally crazy people, and that that leads to both of those things? It doesn't seem to be the case that, say, in the UK, you have large-scale secret hoarding of guns; if that was the case, they'd be closer to use in gun-related homicides, I would think. But just because it didn't happen in the UK doesn't mean it wouldn't happen here."
At that point I realized that I don't know, even in theory, how to tell what the answer to my question is, or what evidence would be strong evidence for one position or the other. I am not strong enough as a rationalist or a statistician.
So, I thought I'd ask LW, which is full of people better at those things than I am. :)
Have at.
-Robin