Badger Johnson said:
I'm now of the opinion you can never 'argue', use facts, use logic on an 'anti-'.
You're absolutely right, but I don't think you've figured out why yet.
There are people who make decisions based on facts & logic,
and there are people who make decisions based on emotions.
You can't use one form of persuasion on the other group & expect it to work.
When 'discussing' with an anti, ask them things like "how would you feel if..." or "what would you do if...", then insert a bad situation*, then be quiet & let them come up with an answer.
Lotsa times they'll realize their position doesn't make sense, but sometimes they can't handle the truth (their stated anti-self-defense position will lead to harm for themselves or someone they love) & they'll get more & more upset with you.
As with other encounters, when you remain calm they look like a loon.
*
(Walking from the restaurant to your car, guy comes out of nowhere running at you holding a large knife.)
(Criminal breaks into your home & you find him in your teen daughter's room, on top of her.)
(You're leaving the state fair & get caught in a violent mob whose members are beating people who don't look like them... and you don't look like them.)