I don't buy it, at least not in the context of ETS.

Entering my 48th year of life I've been attacked by birds, had to beat off some dogs with a stick, been kicked by my horse, fell through ice, had my canoe swamped by a Mississippi River barge, run away from angry bees, and been harrassed by mean 8th grade girls (when I was in 6th grade), but I have yet to have returned fire in order to save my life, nor do I know anyone who has (excluding military service).

To be clear, I enjoy firearms as much as the next guy. I have a safe with several rifles, shotguns, and a few pistols, but they are for hunting and target shooting, but not self defense. Only if there was absolutely no chance of young children being in my home (I have two kids) would I consider having a gun outside my safe. I have never carried a firearm with me while camping or backpacking.