I'm not sure anyone would buy that that wasn't an American themselves. Do you really think it's "just a coincidence" that the country with the highest gun ownership in the world also has one of the highest gun homicide rates? There are other factors, of course. But to say having fewer people with guns would not affect the gun homicide rate is ridiculous.

In any case, it probably would have prevented the Aurora massacre. I think part of the problem is that the US takes money out of health care and puts money into gun availability. So, you have unstable people that can arm themselves to the teeth. Part of the reasons they go on massacres is because the guns are there, everyone has them and owning a gun is something discussed or thought. Canada has psychos, but many of them don't have guns, so it's hard for them to go on shooting rampages. It happens sometimes, but rarely. If you have guns, everywhere, they will be used. The problems in the US are a mix of laws, health care, and the general culture of having guns. Taking guns out of peoples hands won't end the problem. But if guns aren't in many people's hands...it, well, certainly helps the problem of people shooting each other. One only needs to look to other countries. This study said they did that, but then wrote it off as "there are exceptions and other factors so this isn't the answer." Again, that seems to be justifying having the ability to easily buy guns everywhere you go. There is no one-part answer, but it's either stupidity or willful ignorance to say the massive availability of all forms of firepower in the United States is not a large contributing factor to the massively disproportionate amount of gun violence in that country.