You seem to be throwing out these cardboard stereotypes about suicidal people, criminals, old people, everyone. There's such insane variety around any kind of label you can imagine and you seem to be ignoring all of it.

That is true. Even if Slashdot would be capable of providing enough writing space for a ten-volume manuscript, it is still necessary to have a better command of the subject. I am not a professional in this particular area and don't have access to specific, statistically significant cases. My opinion is based on personal observations and on what I read. My opinion may be right or wrong, but I have it and it's mine. And you have yours.

BTW, if your friend is depressed, I don't think you should give him a map to the nearest tall building. You are free to persuade him - and he is free to listen to you or not to listen. Usually people do listen, especially those who don't have physical, material reasons for their decision. (That's what I read!)

It doesn't matter how much you argue otherwise, crime is a symptom of youth and as they age people generally turn away from a life of crime.

... at least because they are not physically capable anymore of the exertion that is required to do it. Quite possible. Still, plenty of young ones around to ruin one's day. And not so young too - look at the FBI's list of most wanted criminals; most of them are well past their teens. (But, of course, those are unusually bad; statistically, they don't matter.)

not only should we not try to prevent it, but it should even be easier.

It's already easy enough. You just can't make it easier. What you can do is to make it less painful. Is the fear of pain a deterrent? Perhaps, to some. But the car exhaust (CO) will kill you painlessly; some sleeping pills (barbiturates) will do the same. Heroin will do you in as sure as a bullet; and not only you won't suffer a pain, you will be rewarded with the final performance. It's far easier for most suiciders to just park their car in the garage, close the door, and let the CO kill them, than to look for a gun and then shoot themselves. It is very painful, by the way, and very messy - shooting yourself is not a good way to leave this world.

The society will not notice the outcome of their decision anyway; there are 6+ billion people on the planet already, it's not like we are endangered species or something. If someone wants to make room, it's their right. Not that I encourage them, of course. They are just free.

I know a guy who committed suicide and a girl who attempted suicide and no one is happy that he succeeded or that she failed

Romeo and Juliet, something like that? Those were successful all the way through. Does the society want them dead? Not really. But, darwinistically speaking, the society benefits from mentally stable people, not from head cases. Those *should* evolve out, in the grand scheme of things. Like taxes, if you support a certain behavior you get more of it. There are people who try to commit suicide repeatedly (and fail N-1 times out of that.) Then firemen are summoned, the police, and the doctors... what for? In the USA the Constitution guarantees your right for pursuit of happiness, but it does not define what form it may take. If you cannot live without your man|girl, don't. Will I be sad? Probably. But I cannot tell you to suffer for years, if not for the rest of your life, just because it is in my personal interests, either political or religious, to keep you alive. That would be awfully selfish of me. On that subject:

can't you at least acknowledge that more people killing themselves is a bad thing?

Bad thing... bad thing... bad to who? What metric are you using, and whose viewpoint? Per the blind and deaf quadriplegic, his life is over already. Per his brother, he must be kept alive until brother's own child can inherit his house. Per his wife, he should die immediately, so that she inherits. Per his aunt, Jesus the God personally told her that suicide is a sin, so the poor injured man must be kept alive for as long as possible - even though he suffers physically and mentally. Who is correct here, in this sea of incompatible interests? (This is a dramatization of a real world scenario that played out in Florida.)

So when you say "bad thing" you need to qualify this statement. The nature doesn't have bad things. Things can be declared good or bad only by an observer who has an opinion.

Actually I'm guessing the ones who don't get caught or killed stop on their own once they pass their mid-twenties.

I'm not sure where you live, but in most countries criminals cannot stop. There are the usual socioeconomic reasons for that. There is not enough jobs even for citizens who never jaywalked. What chance, in your opinion, a man with a burglary or a theft under his belt has? How many store managers will be happy to give him the keys to the money box? The only jobs that are left for them are menial jobs, like digging of ditches. Maybe one can become a licensed professional, like an electrician or a plumber, but that's not easy - there is a requirement for apprenticeship, and with that see above.

Can a criminal reform? Yes. Most of those success stories are from white collar crime, where for example an accountant made a "mistake" toward his own bank account. Just once in his whole life. He won't do that again. Kevin Mitnick is a good example. Some violent criminals embrace religion in prison and also become ex-criminals. The vast majority, however, is stuck in the vicious circle forever. They don't know how to live differently, and the society rejects them even if they try to end their wrong ways; they become career criminals.

With regard to "hardened killers", there is no shortage of those. Gang initiation rituals sometimes include killing of someone. There are obvious reasons for a gang leader to require that. Many homeowners are injured and killed during home invasion. Nobody would be concerned about an imaginary problem; the people are concerned because the problem is very real. It is exacerbated by the fact that most homes in the USA are open to anyone; you are separated from the street with just one flimsy glass door. Burglars throw a stone through that door (in the back of the house, usually,) and if nobody comes out to investigate then they come in and gather valuables. If you are unfortunate enough to catch them in the act, they may kill you. Many burglars are desperate druggies in search of money to buy another dose; they won't even consider your life sacred; they will kill you for $10 (that has also happened.)

I cannot say much about the distribution of violence among criminals. But my own understanding is that meek criminals do not exist. They simply cannot survive among their own kind. If they are lucky enough to get arrested early, they are most likely to mend their ways. The survivors, on the other hand, are someone to fear - they are graduates of a school that does not forgive a weakness.

Gene Roddenberry was never very good at going more than 40 years into the future with any of his technology detail predictions.

It doesn't really matter how far into the future the author of the script is looking. The only thing that matters is how the viewers are going to accept that.

Try to make a movie today about a programmer's day at the office, and then show it to the audience of 1900's. Will that work with them? But a good old western will work because the audience understands what's going on. You can look 1,000 years into the future, where humans become invisible energy beings. How do you film those?

Is it feasible that the Starfleet insignia doubles as a communicator, but is not able to transmit video - or even still images? That you cannot triangulate on that signal? That it cannot automatically report medical trouble? These functions are already common among special operations troops, even though we haven't mastered the art of subspace communication yet, as far as I know. But these, and many other omissions and deficiencies give the script writers the tools to construct situations where the protagonists have to actually invent a solution, instead of casually teleporting away from danger. The same story happened to K-9 and the sonic screwdriver of Doctor Who - they became a universal solution to all the problems. That's why the Doctor gave them away. (No sane person would do that, of course, considering how often these devices saved his $behind.)

Should the you who's having a really crappy day have the power to kill the you who will have a lifetime of other days?

Unconditionally YES. No man can be called free if he doesn't have this ultimate freedom - and the responsibility that comes with it.

People have moments of weakness, if possible I'd like to make it less tempting for those moments to end with their own death.

I believe in free will and self-determination. It is wise to keep dangerous temptations away from children - they don't know any better. But once a person becomes an adult, this restriction is lifted and he is free to do whatever he wants - as long as it doesn't clash with the same right of someone else. If he was wrong... too bad, he should have asked for an advice, or perhaps he should have thought about it a bit more. If someone, after all, suicides - respect his decision; he had his reasons; one day you may have yours. None of us live forever, as far as I know, and not everyone is excited about spending his last ten years of life in a bed, paralyzed, unable to even eat on his own, and over those ten years burning through the entire education fund that was being saved up for your grandchildren. When your time is up, it's up - deal with it. Many suicides are just an easy escape from a painful and terminal illness.

If every criminal is armed, and constantly committing home invasions, then sure, I might be in favour of a lot more guns, but I don't think that's the world.

Do you think criminals commit home invasions just on some special days, like Santa Claus? They go out and burglarize residences until they are caught or killed. There are very few criminals who were successful for a while but then, before they were arrested, suddenly saw the light and became honest workers. Most soldier on until stopped. Criminals are not very smart. Smart people don't need to rob houses; we get paid big bucks for sitting in our chairs and pressing keys on the keyboard.

By the way, all criminals are always armed, as far as the victim is concerned. Not everyone carries a gun, but a crowbar will be plenty sufficient for an old man (that happened too, and more than once. Burglars don't like witnesses; dead men tell no tales.) I read that knife crime in UK is off the charts, and I can understand why - knives are cheap, silent, deadly, easy to make, and easy to dispose of. Gun crime is also rising as a side effect of that - criminals need guns to defend themselves against criminals with knives. It's not a mutual appreciation society, you know.

With strong gun control, even if a few tragic scenarios happen where someone could have really used a gun, I think a lot more tragic scenarios will have been avoided.

We are firmly in the land of hypotheticals at this point. I'd better stop now :-)

I swing a bat the inertia is going somewhere, that somewhere is the intruder.

My point is that the inertia is a two-edged sword. You cannot redirect the strike when the target moves. That's why karate fighters don't usually swing huge tree trunks around. It's fine if you can do it and hit the opponents; but if the opponents are not drunk you will not hit them at all, and your weapon will pull you to the side.

You're expecting the average person to shoot the criminal in the eye of their choice while the criminal has a close family member at gun point

No, not at gun point. Even the police is not going to go head first into that situation. You need a sniper now, and a hostage negotiator. Your task is only to prevent the criminal from taking a hostage. If you can do it with a bat, more power to you. I'm not that brave.

With regard to accuracy under stress, it's easier to do if you have a superior weapon. You can always try to defend yourself and your family with scissors, but YMMV.

If you are questioning just the technical accuracy... it's trivial. The typical distance for handgun targets is 10 to 25 yards. Test yourself one day.

Suicides are more likely with guns, that's actually reasonably well established (and kinda obvious).

If someone wants to kill himself, he will do it eventually. And if someone doesn't want to kill himself, a gun will not hypnotize him into that. I, personally, don't care either way. A free man has power of life and death over his own body.

I like how you're crediting the steady fall in violence in society to the advent of firearms.

As they say, "God created men; Samuel Colt made them equal" :-)

It's big, heavy, and probably metal.

It's also useless, unless you are The Incredible Hulk. A man with a bat loses 100% against a man with a small pen knife. Intertia is not your friend. I know that it's possible to do fencing with heavy weapons, but it requires a very uncommon physique. This article could be useful, even though it talks about an edged weapon. A blunt weapon, like a bat, is far less useful in a battle.

Swing with two hands and an adrenaline rush and you don't risk missing and killing one of the kids

Get a heavy pipe and try swinging it in your small apartment, I dare you. It is just not feasible; houses are built with narrow hallways. The target of your attack can just lazily step aside, and your swing is wasted. Unless you are a second coming of Terminator, you will not be able to control a heavy weapon, with one hand or with both. Your advantage would be in a light weapon, with katana being on the heaviest end of the spectrum, and a rapier on the lighter end. With the latter you can easily defend yourself against multiple attackers, assuming that they don't have ranged weapons. A rapier will be also very accurate in thrust style attacks, so that you can work around the hostage.

Oh, you said "kids?" Well then, imagine that the criminal is holding your daughter. With a handgun, from several yards away, you can hit him in the eye of your choice, and the hostage will be only slightly scared. Can you swing a heavy bat at the same criminal when he can always push your kid under the strike? When I said "overwhelming force," there is a reason for that. This is not a duel between two French aristocrats; it's not a game.

Besides it's a contrived situation. Given me and the criminal both having guns and me and the criminal both having a bat I'll opt for the bats every time.

It's your life, even if somehow you can convince the criminal to have a bat (that is hard to conceal) instead of a knife or a handgun. I'm just telling you how, in my opinion, the conflict will unfold. I have no dog there.

Besides, even if Trayvon was beating a man who was down that's a long way from murder, sure it might have eventually resulted in death, but most likely the worst case was some broken bones and a concussion.

A strike in the head is often fatal - instantly, or a short time later. There are several medical reasons for that, and none of them are particularly pleasant to discuss.

Russia isn't exactly a model of good governance.

It's worse pretty much everywhere else, except a handful of countries. But even in the UK the percentage of gun crimes is rising with every year. The situation in the USA is much worse still.

Most of the criminal firearm problem in North America is due to guns coming in from the US.

Then please ask Obama to stop sending weapons to Mexican mafia. But regardless, Mexican narcocartels are rich enough to buy their full-auto weapons anywhere in the world. You simply cannot get most of these weapons in gun stores in the USA.

Criminals don't come from another planet.

Mathematically thinking, they actually do. The fact that they were born here is not relevant; their minds are out of this world. You can also say that your mind is out of this world, depending on what mindset owns this planet :-)

They have guns because Americans say guns are acceptable, even cool, they have guns because they're really easy to get so you don't have to be part of some sophisticated underworld because they're floating around everywhere.

Criminals have guns not because they watched TV one day, and their favorite hawk Piers Morgan told them, in plain text, that guns are cool. Criminals get guns because guns give them power over people who have no guns. That's the same reason why police and army have guns. Power is the end goal, not the pleasure of lugging a pound of steel in your pocket. (Yes, it is heavy and uncomfortable. I guess you never tried...)

As I said, guns are always easy to get for a criminal. He is already in that "sophisticated underworld," where drugs, weapons and everything else is available for a reasonable price. Do I know where to get a gun with removed s/n? No, I do not - and I have no need to know, and it's illegal to own one anyway. But criminals don't care about laws.

Every extra gun makes everyone else a little less safe.

There must be rivers of blood flowing down the streets of Swiss cities... and those poor American colonists, how did they survive, being 100% armed?

By having a gun you're maybe making you and your family more safe

Q.E.D.

(more likely less safe with suicides and accidents)

Suicides are going to happen anyway; it's just less painful with a firearm. But if you insist, a cancer sufferer can throw himself from a roof of a tall building. Accidents with firearms are extremely rare; statistically they are not even a blip on a radar. Car accidents are 10,000 times more likely and more deadly, but we don't ban cars (yet.) Nothing in life is free, and Darwin clearly explained how his laws work. If you are inclined to do the "Hold my beer and watch this..." routine, do not be surprised that you hurt yourself in one way or another. IQ is required for survival, even if you just are crossing a street.

but you're most certainly making my family less safe.

My calculations show the exactly opposite effect. If a neighborhood is known to have guns, criminals will be less inclined to break into them because they are not sure who is at home and who is armed. This means that if your family has no guns, but your neighbor does, and that is known, you gain protection.

On the other hand, if a house or a neighborhood are known to have no guns, any gang of burglars can waltz in at any time. If there are homeowners, they can be beaten up or better killed, so that there are no witnesses. There is no danger. Therefore I can claim that you, by having no weapons, and by not opposing the criminals, are endangering everyone - and myself.

And one more thing. Let's for the moment imagine that *all* firearms disappeared from the planet. Perhaps the powder does not explode anymore, like in Amber. What will the criminals do? What will the police do? What will the peaceful, innocent citizens do? Would you want to live in such a world?

This, actually, was the case before firearms became common - from the first days of human history and until, say, 1700's. It was a sad time for anyone who is not a trained fighter. I will not waste space here on retelling the history of middle ages, but you get my drift. A Burgher is not safe in his shop, unless he surrounds himself with hired swordsmen. A family of a laborer is just a prey for dagger-wielding dwellers of the bad part of Ankh-Morpork. Murdered citizens were daily (or nightly) occurrence in large cities. The life belonged to young and strong. Do you approve that message?

I have 14-kde; GNOME just doesn't work for me. Too simplistic, perhaps. I was always leaning toward KDE, and its C++/Qt base was far richer than the objects made by hand in C (GTK.) I'll get one to try again, though, just to be educated.

"The man was Asian; he was not raised in the USA, and probably he believed that the government will protect him. He took that belief to the grave." -- Really?

Hard to ask him now.

Dude, I come at you swinging a bat with a bit of surprise and unless you have some serious martial arts training I win.

There won't be any surprise in most cases of self-defense. If anyone is surprised, it would be the victim. The criminal is fully aware of everything because he initiated the situation.

Now about the bat. Make one for yourself out of packing foam, grab a friend and play that out. You will be defeated after the first swing, most likely.

Why is that? Because you cannot, probably, hold the bat in one hand, like medieval warriors held their swords. (There were two-handed swords too, but that's a different story.) A bat just doesn't have the right balance for one-handed operation. The medieval fighter held a shield in another hand. That part is essential. What happens when you grab the bat with both hands, take a swing - and miss, of course? YOU ARE EXPOSED to an instant knockout blow to your head, and you have nothing to defend against that blow because your both hands are holding the bat - and the bat is on trajectory away from the target. You don't even have a fellow soldier to the right of you, watching your now exposed front and right side. You are dead meat.

The nearest match to a bat among medieval weapons would be either a club, or a mace, or a Morgenstern. You do not know how to correctly wield those. Hardly anyone has that skill today. Huge inertia of these weapons requires special handling. Without this knowledge and skills you will lose, instantly.

It would be awfully arrogant to assume that one can just grab a piece of wood and become an invincible warrior - despite humanity's thousands of years of experience with exactly these weapons. Criminals know more about fighting with and without such weapons than any green-skinned programmer, fresh from a cubicle. You will not win. If you want to win, use overwhelming force, just once. Use the weapon that you are familiar with. (You are always welcome to train with a bat - but not on a baseball field. You'd have to train for combat.)

Trayvon nearly killed a man??? At most he started to lay on a beating, assuming it would have escalated to murder is ludicrous

That was alleged, however little we know so far. The trial will expose everything that transpired, and then we will know for sure. Meanwhile, it does look like Trayvon was beating a man who was down. How much of head trauma are you willing to take before you depart into the better world?

Criminals have guns because they're friggin everywhere because you don't have gun control. Get serious gun control and there's no guns for the criminals to get.

I was born and raised in a country with very strict gun controls. Even today a common man cannot have a handgun there. Still, criminals always had handguns. Where did they come from, one may ask?

1. From World War II battlegrounds. Many full-auto weapons can be recovered and restored.
2. From warehouses of the army. There are millions of firearms stacked sky high, in crates, oiled and ready to go. A crate more, or a crate less ... who will ever look inside?
3. From current stocks of weapons issued to guards, police, army, etc. Some of these weapons are genuinely lost, but most are taken away after killing the owner.
4. From modern war zones, inside and outside of the country. Africa specializes on second hand weapons, they have many millions in stock. Thanks to Obama, there are a few thousand more in Mexico now.
5. Manufactured domestically. A modern CNC can make you a firearm with a single press of a button. But one can make a zip gun out of Home Depot components. That'd be enough to shoot a police officer with it and capture his factory-made weapon that is good for tens of thousands of rounds.

Even if you take legal firearms away from everyone on the planet, manufactured firearms will be still with us. Do you want to go with bare hands and best intentions against a man with a homemade pistol? Whether you like it or not, weapons are part of humanity, for many reasons. You are free to refuse them to yourself and your family, but that has no effect on others. Your political decision may have your family injured or killed. Consider that.

Pepper spray just says I want the fight to end.

[Channeling Bush...] "Who cares what you want?" - the criminal is not interested in the fight to end; he now wants you dead, even if a moment earlier he'd be content with just maiming you.

Most likely he'll just do nothing (which is why old people tend to be victims).

Old people are more likely to be targeted than Arnold lookalikes. Among those who are targeted, some are fighting back, and others do not. There was an old man who was killed by a gang of feral teenagers - they were playing their "knock-out kings" murder game. The man was Asian; he was not raised in the USA, and probably he believed that the government will protect him. He took that belief to the grave.

Depending on his size I might first grab a bat or other object and start pummelling him.

It would be patently insane. What if you lose? Just stop and think about it for a moment. There are very few people on this planet who can take a bat and be sure that they defeat an intruder. In most cases the intruder takes the bat away from you and then uses it on you - this is an unfortunate quality of a contact weapon.

Besides, you throw away your gun, grab a bat... and then the intruder pulls out his gun. What happens now?

Remember, your duty is not to the intruder, it is to yourself and to those who you protect. You are allowed by law to use deadly force only if you fear for your life. If you do, the threat is large enough to use that deadly force.

If you do not think the threat is that grave and you can get away with using a bat, this *legally* converts the situation from self-defense into a banal quarrel. The intruder then can sue you for millions if you hit him with a bat and break his arm. This has happened before. You always need to know on which side of the fence you are - are you afraid for your life or not? You cannot claim one but act according to the other. It's the legal divide between going to prison and staying free. An armed confrontation is not the right time and place to think. You have to have the thinking done ahead of time. The only thinking you can afford is to match the situation to one of templates that you prepared ahead of time. If you start thinking deeper, you will lose - your actions will be examined under the microscope in court.

Pepper spray simply inflicts pain, very intense pain, to the eyes no less. You can't just ignore that,

As I said, many street drugs reduce sensitivity to pain.

Besides, if there's enough guns around that the victim has a gun then wouldn't the perpetrator have one too?

Those are statistically unrelated variables. You should expect the perpetrator to have a weapon on him. It does not matter if it is a gun or a knife or a pipe or just his fists. See Trayvon's example - he nearly killed a man with his bare hands. Trayvon was a tall and strong football player, and his victim was a short and skinny Hispanic.

Regardless, criminals already have guns, and they will always have guns, as long as it benefits them. If you disarm yourself, this only makes their job easier. A and B are not related. Get a gun, know how to use it, and establish for yourself very rigid scenarios where use of a gun is required. Then you will be prepared.

Oh, by the way, often home intruders come as a team. I wish you luck fighting two or three guys with just a bat. You will not win that, unless you were trained in Shaolin Temple.

Thanks for the good advice!

I would be interested if this experiment was reproduced by several respectable researchers, but the skeptic in me says that this will likely not happen.

You can always try the experiment yourself. Your local Home Depot (or equivalent) has a good selection of seeds, and the seeds don't require much attention. You can even buy exactly those seeds at Amazon for a princely sum of $1.89.

Uh, quoting is nearly entirely useless in Outlook, "discussion" is one of the things it is about the worst mail client for.

People have adapted to top posting. After all, they are most interested in what *you* have to say, not to what tens of other posters said before you. This works well enough for most small discussions. If you expect a larger discussion, email in general is not a good medium for that.

Also you can include screenshots in plain text mails, just not in the middle of the text.

Loss of continuity. I often have to insert screenshots. Referring to separate files is not convenient. A single story is better than a patchwork.

there are far too many people who throw around images like crazy so that finding the actual text to read is like am Easter egg search.

This is not a problem in business communication. At the same time, "actually explain stuff in text" is not sufficient - a picture is worth a thousand words. Note that in engineering a misunderstanding can be very expensive. You always want to be very specific, and every instruction that you send to techs must be very clear. Those techs are not rocket scientists; even if you explain it in text, they will come back and say "I don't understand what you wrote here." But a crude screenshot from your CAD, with a large red arrow scribbled on it with a shaky hand, will do the job. As they say, "X marks the spot" - not "count three large thingies from the left and seventeen small ones, then go up by thirty three medium thingies."

Also, rich mail completely breaks things for people who want to read e.g. green on black

Yes, it does that. Some of that is configurable, though. Other you have to accept as it is.

So no, rich text does not make it a good MUA for most people, because most people are unable to use rich text in a way that is a win.

Yes, most people cannot use rich text in the best way possible. However rich text *is* a good solution for them because it allows them to use it when needed. Nothing stops people from sending in plain text by default from Outlook - it is configurable. But they use defaults, and they are happy enough with that. Rich text is a superset of plain text, and it is not fitting to argue for *removal* of features just because the unwashed masses are not yet mentally capable of using them as I think they should be used :-)

Give a hundred old ladies guns, and another hundred old ladies pepper spray, and have rapists go after all of them (ethics review board might have an issue with the experimental design). I wouldn't be surprised in the pepper spray ladies did better.

"Your wrong," as it is customary to say here. Police trainers always tell their students that even a mortally wounded attacker may have enough strength left to cross the few yards separating him and the shooter and to kill the shooter with his bare hands (or a knife, or a gun.) This has happened before, more than once. Why? Because that attacker has nothing to lose, and he certainly has a solid revenge motive.

There is another expression: "Don't attack an old man. If he is not strong enough to fight you, he will kill you." There is not much that the state can threaten a 80 y/o man with. Besides, every jury will be on his side, and against some 19 y/o attacker(s) who wanted his cell phone or his c/c.

I'm a guy but I have a lot of trouble thinking of a scenario where I'd actually shoot someone who hadn't already taken the first shot, ie at best my gun would be a bluff.

You wouldn't shoot a guy who broke into your house, tied up your wife and is now doing the same to your two teenage daughters?

Also, don't think that women are somehow more pacifist than men. They may be less likely to attack unprovoked, but they have an instinct to defend their family - and that instinct is often stronger than among men. Just this week a woman stabbed an intruder to death with a kitchen knife, while her husband was experimenting with non-lethal methods of persuasion.

a few of the bolder ones will realize she isn't willing to shoot, and they'll probably be right. With pepper spray fewer will run, but almost all of those who continue will end up with a face full of pepper spray.

Most of those "bold" ones will quickly become dead ones, and the homicide will be written off as justified. With pepper spray many of the attackers will end up with a face full of it ... but the victim will be raped and then probably killed. At very least, the victim will be pepper-sprayed by the attacker to teach her to not do that ever again.

I guess there is no way she could own a knife also. Or pepper spray, or a taser, or mace. Without a gun the elderly are generally helpless against a knife wielding rapist?

Let's presume that the rapist is not a 90 year old man, and that for some reason a younger man wants to commit this crime. Do you think a 50 y/o man *without* a knife would have any trouble with a 90 y/o *with* a knife? Knives require a certain level of proficiency to be effective, especially in a fight at an open space (not in someone else's kitchen, in darkness.) A career criminal can be expected to know basics of knife fight - those long years in prison had to be used for something, after all, and everyone there is a teacher. How many women even know how to grip the knife correctly, or what stance to take?

Pepper spray is notoriously ineffective against people on drugs. Taser is a device that, in ranged mode, has to be aimed and fired; dense clothing often is a sufficient protection. In contact mode taser is not a weapon at all because if the victim can touch the attacker, then the attacker can also touch the victim - and he will not be gentle at that.

A firearm is a superior solution because it releases far more energy that it takes to pull the bang switch, and it is effective at all practical threat distances, and there is no commonly worn protection against a bullet. If an attacker sees a 9mm barrel pointed at him, he sees imminent death. If an attacker sees a pepper spray or a Taser, he knows that these are not a threat to his life, and interprets it as a challenge, as a game that his prey wants to play before giving up. Also, if the victim manages to hurt the attacker with these ineffective defenses, the attacker will be very, very angry - and fully capable to prove that to the victim.

Sorry, but your intent was entirely unobvious, especially in the context of this thread. Exchange servers do go down, after all, and the question that you posed is entirely valid.