Piece at BigGovernment.com: How Obama Reduced Crime Rates Last Year

My newest piece there starts this way:

President Obama surely didn’t intend it, but he deserves some credit for last year’s 7.4 percent drop in murder rates. His election caused gun sales to soar, and crime rates to plummet.

While gun sales started notably rising in October 2008, sales really soared immediately after Mr. Obama won the presidential race. 450,000 more people bought guns in November 2008 than bought them in November 2007, that’s over a 40 percent increase in sales. By comparison, the change from November 2006 to November 2007 was only about 35,000. Over the last decade, the average year-to-year increase in monthly sales was only 21,000.
The increase in sales continued well beyond November 2008. From November 2008 to October 2009, almost 2.5 million more people bought guns in the 12 months after the election than in the preceding 12 months. The National Instant Criminal Background Check System, or NICS, doesn’t tell us how many guns each person bought just the number of people who bought them. Most likely though, gun sales rose by more than the number of people who purchased them. . . .

I should have included something like this in the piece. The impact of guns on crime rates can be due to multiple factors: 1) People using their guns defensively will prevent attacks from becoming crimes. So even if the number of attacks remain the same, the number of recorded crimes will fall. 2) Some criminals may gradually learn that the risk that they face from individuals being able to defend themselves is increasing.