Violent crime is an issue far too complex to be boiled down simply to firearm restrictions when examining different countries.
Webley nailed it. I was in Vancouver when a large study was done comparing crime between that city and neighboring Seattle. The study mentioned that Seattle had a higher rate of suicides involving handguns, and that such a finding "proved" that lax gun laws led to suicide.
Even the most liberal Canadian professors I spoke with called shenanigans on that conclusion. There are simply too many differences in culture and demographics. In addition, Vancouver was not the conduit for opium and its derivatives in the way Seattle was.
Take Denmark, where I lived for a time. It's a largely homogenous and devout society, with a strong familial bond and a shared heritage. The standard of living is high, and the population is somewhat small.
(They also still respect jazz. The real stuff, not that David Sanborn drivel. I really think that has something to do with a culture's well-being
Compare that with the staggering number of contrasting cultures, belief systems, disparity of wealth, and dense population that we have in New York city. Is New York more violent than Copenhagen? You betcha. But it's not because of the mere presence