I'd love to see some supporting evidence of this, particularly to separate the causation/correlation problem. I'm not disparaging your viewpoint, but I just personally believe that gun ownership and crime rates are relatively unrelated. Crime rates tend to be directly related to poverty levels and the quality and innovative tactics of local police forces.
New York City is an interesting example. Here we have one of the safest big cities in the US (and the #1 safest of the mega cities), and I'd postulate that gun ownership here is actually quite low among most of the population- I don't have specific backup here, but I'm basing this on the general political leanings and issue support of people who live here. In fact, NYC has recently passed even more restrictive gun-ownership and purchase laws as compared to the rest of the country- including an interesting one that requires gun dealers to file bi-annual inventory reports with the NYPD.
20 years ago NYC was one of the most dangerous cities in the country. There are a variety of reasons as to why the place improved, all of them have been debated in the area over the past few years (particularly as Giuliani has tried to take credit for all of them
), but none of the cited reasons has been increased gun ownership. I can't any supporting statistic for this, but I wouldn't doubt that gun ownership has dropped over time among honest law-abiding citizens.