The problem with this analogy is that it's actually the wrong way around. The problem firearms are the handguns - the US has 17k murders per year, 13k of them are with firearms, 11k of those are with handguns. Much as people like debating about rifles, it's handguns that do the work.
You politely ask people not to get pedantic then the majority of the discussion becomes pedantry. Instead of replying one by one I'll lump a lot of responses here.
1. The millimeters on my defensive gun were very off. I don't know about guns. Just imagine a typical handgun.
2. The handgun analogy is not about how much damage one causes over the other nor is it about the severity of the consequences. The point is that we can all relate to the average homeowner buying a handgun for protection and most people can understand that and trust that your neighbor isn't buying it to commit crimes. But when your neighbor buys an assault rifle and claims its for self defense you start to wonder because we all know, on average, most of the time, it's common sense, stop being fucking pedantic, that assault rifles are not for self defense and when someone claims that it should set off alarm bells just like when someone says "I only used MegaUpload to share Excel spreadsheets with my coworkers and so did everyone else I know or have ever heard of" you've got to wonder if that person is living in a bubble or just straight up delusional.
The point is that we can all relate to the average homeowner buying a handgun for protection
Can we? Where I live, buying a pistol or an assault rifle for self-defence would get you viewed the same by your neighbours. I'd actually be more concerned if I heard someone on the street brag about their pistol because it's much easier to carry about secretely than a rifle.
This reminds me of the term 'security theatre', which is why I think the analogy is a bad analogy.
