really? I would generally think that irrational people who panic that are armed will do a lot more harm.
Society loves to make excuses for itself and it’s idiotic behavior. Damn that MTV to hell. No, kidding aside the majority of those that carry are far from irrational in my experience. Also less prone to panic as they are more prepared for the shit to hit the fan. Being prepared for the worst often prevents it from happening in the first place. Those that carry on a regular basis have respect for the weapon and understand the responsibility it brings. A criminal is more likely to go get a weapon as needed, not have one on them. If more people were armed and capable of defending themselves do you think criminals would be as eager to mug or approach?
My 2 cents.
not really… the guy who gets home early from work to find his wife in bed with another man is more likely to go to jail if armed, amiright?
or maybe the guy who’s banging your wife finds your loaded gun / knife under the pillow and panics?
LOL. Much to specific an example. Sounds like someone is plotting something, no? J/K
If you play with fire sometimes you get burned. If people were more honest and didn’t cheat there would be less beheadings and murders for sure. 
What if the other man was armed and you walked in and were also armed and a knife fight ensued. All’s fair in love and war.
my example has a simple… without the weapons with with the irrationality you end up with a black eye.
I don’t want to ban guns and knives… but I don’t feel unprotected without either.
Nor do I. It’s a right I choose to exercise and not due to cowardice in the least. I don’t need a knife to protect me. One could make objects laying on the ground as lethal as a knife if not more so. It all comes down to understanding consequence for your actions and being responsible in choices you make. Using your example of infidelity…if you aren’t banging another mans wife in his home you have nothing to fear when the husband comes home…whether he is a knife collector or not. Infidelity is just as much an impulse control issue as pulling a knife on the intruder would be. Anyhow for that job I would probably use a baseball bat personally. LOL
Fair enough? 
A knife to me is a lot more useful. If I’m in a questionable situation I can pull my knife out, and start digging at my nails or something like I have a sliver, but yet you just showed that you have that item at your ready.
People have threatened to “kick my ass”, I just asked them how a pen in the arm would feel.
Once you pull a gun, you have broken the law in the police’s eyes. You need to prove you had reason to pull anything like that out.