Apologies. I don’t mean that they are equally effective at harming, I’m referring to the fact that it doesn’t matter what weapon you choose, the fact is you are against aggression, NOT firearms. Also, there are people who control whether or not you can join the military, I cannot join.
(As a non-American I've kind of taken to distancing myself a bit from this particular debate, plus I also see it as a bit futile a debate, guns in the US are there to stay, unless gigantic pyres of guns are gathered, UN-in-Africa style (and even those are mostly for show, but I digress))
That said, the argument is usually refering to the efficiency of guns - which is undisputable. When someone argues "remove guns, and there will be more stabbings", my thought is always - okay, fine... stabbings are marginally preferable. I'd rather be stabbed in the head, than shot in the head (to be absolutely clear, I'd most rather not be stabbed OR shot in the head)
The anti-gun arguments focus on the guns because of the very efficient delivery of bodily harm, across a distance, and at the speed of sound(!)
Try stabbing someone fast enough to cause a sonic boom. People who are struck by bullets typically had absolutely no physical oportunity to move aside, even if they knew it was coming. With a knife there's a lot more scuffling around, you might lose the fight - many do, many succumb to stabbing - but it's much more survivable then having someone point a rifle at you, at 3 metres distance, and then simply decide to pull the trigger, there and then.
I get your more philosophical argument though, I do, and like I said, I don't *really* have a dog in the American-guns-race.