No need to get your hackles up.
It is a perspective thing. I don't live in the US anymore and partly it is because of the high rate of death and injury due to the gun laws, and partly it is because (due to all that death and injury) I had found myself coming round to your way of thinking. It is kind of self fulfilling, I suppose. Everyone has the right to carry, so everyone does, so lots of people use them, so everyone needs to carry one.
I had a neighbour who told me about the guy who lived two doors down from us. He'd got into an argument over parking with his neighbour. An exchange got heated, so he went back into his house, came out with his gun and shot his neighbour. Not fatally or anything like, but he went to jail. There's the problem. Ordinarily a perfectly civil character. Now his kids get to see him wearing orange. Your self defense argument raises the ante too high in some ways, but in other ways, people are too attuned to the shooting.
It was notable yesterday, in a depressing sort of way. The shooting in the Maryland newspaper was the fourth item on the BBC radio news that night. Fourth! After stories about Brexit, the World Cup and a royal visit. When did it happen that happen that a shooting like that just falls off the news cycle? It is like everybody is becoming numb to it, and there's little can be done. I was watching a YouTube thread about hiking the AT the other day and the difficulties/inconveniences of carrying a concealed gun. Perfectly sane discussion on different state permits and what it means to be carrying a gun in your pack rather than on your hip or under your arm ... the Q&A in the comments quickly turned into a civil liberties squabble. So quickly, so kneejerk, that I really did have to wonder what the discussion was actually about.