Yeah, it's silly. But, if guns kill people, why hasn't there been a huge spike in gun crimes corresponding to the huge spike in guns bought last time around?
Only the most extreme anti gun zealots think there is a one to one relationship between guns and crime, such that more guns will always lead to more crime, drowning out every other possible factor contributing to the crime rate. Those people and those that argue the opposite (that more guns necessarily equals less crime) are fringe and absurd. Many factors help explain crime and social scientists have not carefully pinpointed all of them.
It may be more useful to look at differences between the overall crime rate vs the number of people shot; there is some evidence that while overall crime dropped from 2002 to 2009, the number of people shot remained the same or increased slightly, in contrast to the 1990s when the number of people shot fell sharply along with crime. On the other hand, gun rights advocates can argue from some evidence suggesting that we have gotten better at treating gunshot wounds so that the mortality rate from being shot has fallen. Also, while the number of gun sales increased from 2002 to 2009, the number of accidental shootings has not increased. So gun owners may be doing a better job at safety than before. There is a two to three year lag in the release of public health statistics and much of the new buying has been in the past two years, so I think the jury is still out on the impact of all this on public health. The political chill on funding to do gun studies enforced by the gun lobby certainly hasn't helped our ability to understand things objectively.
