Making access [to firearms] more challenging, and giving those who seek access more scrutiny, will dissuade those who seek to do harm from even trying to obtain these weapons. It will not stop the most motivated of individuals, it will not stop all crime, but it will reduce the frequency and severity of the problem, as well as inject some much-needed responsibility into the existing gun markets. No other product that has potential for so much harm is sold with so little oversight, or even liability for misuse, theft or loss.
Springer marshals evidence that gun control laws have little causal effect on gun violence:
Here’s a cautionary tale – one very similar nation has a homicide rate of 9.8, more than twice that of the US. That nation was the US, in 1991. What changed? Sociologists differ, but it was certainly not due to stricter gun laws. (One frequently-mentioned and surprisingly robust possibility is reduced childhood lead exposure after lead was phased out of gasoline.) Simultaneous declines took place in many other developed nations to various extents. If non-gun factors can change the murder rate within the same country by more than a factor of two, it is extremely challenging to say anything about the effects of gun laws in nations with very different cultures, histories, economies, and demographics.