Naturally there are less suicides via firearms when firearms are verboten. Firearms may be more fatal than hanging (the most popular method in the EU), but we’re comparing a death rate of 14/100,000 to 10/100,000 which really isn’t that different (and in fact some EU countries like Hungary and Belgium outpace the US avg dramatically, Idk what is happening in Hungary but it’s comparable to our ‘Suicide Belt’). From what I read, hanging has a 70% mortality rate while firearms have a 90% rate, so when adjusted for failed attempts (since I cannot find the actual numbers of attempted suicides) we get 15.5 in USA vs 14.3 in EU per capita. As for other acts such as domestic disputes, fists are far more prevalent because the intent is rarely to kill, and all households have knives if the intent is to kill, so I’m not sure if firearms are a major factor in the actual rate of disputes.

As such, we see little raw change in human behavior. Firearms do not increase suicidal ideation nor intention, they merely provide a more fatal means to do so (although, given the health complications of a failed hanging I question whether the ethics of this outcome are truly superior). So I really don’t consider the argument that restricting a population from firearms is good just due to that, when the method of suicide is independent of the reasons for suicide.

As for #1, cars are still widely accessible, and those who go on murder sprees would have far worse chances if more people carried weapons for self-defense.

As parent stated, these bans do not meaningfully change human nature, they simply give an air of safety. In fact, I would further say they create bad habits within society that criminals can and do exploit. Do you have a meaningful way to protect yourself if you were attacked? You should, your safety is a God-given right that only you can properly defend in the heat of the moment. Does your place of residence not allow for self-defense? Then that is a flaw in governance that must be addressed.