All that is wrong with owning guns.
Firearms have two main purposes. One of them is sporting: hunting, skeet and target shooting. These ritualized sports are of no more danger to the society at large than judo or fencing.
The other most important purpose is self-defense. The definition and reality of self-defense is reluctant participation. The same people who learn to handle firearms, usually hold certifcates in First Aid and CPR. That does not mean that they are just waiting for others to choke or suffer a heart attack. However, if someone around them does have a problem, they can help.

People purchase guns out of necessity, much the same way they buy accident insurance and fire extinguishers.

No one wants to spend $400 for a handgun and $30-40 each month for ammunition and range fees. No one in the United States wants to go to work burdened by a 2-pound chunk of metal and plastic. No one in Israel wants to lug an Uzi and four spare magazines when going grocery shopping. However, people do so to avoid coming to grief at the hands of the few violent felons who do not value lives and well-being of others.

I would like to comment on several popular views about firearms.

If only firearms were outlawed, many social problems will disappear.

Firearms are tools, not causes. By the same logic, banning needles will prevent drug use. In reality, druggies would use alternate delivery methods, while diabetics who need needles to inject insulin would be out of luck. By the same token, violent felons would still have guns or switch to edged and blunt weapons, leaving law-abiding citizens vulnerable. For better or for worse, guns are effective equalizers.
Nobody needs a machine gun for hunting Bambi.

Primary purpose of personal weapons is not hunting but preventing criminals of all ilks from hunting you and your dependents. And effective weapons, up to and including machine guns, are very helpful in keeping you and yours alive in the face of adversity.
Guns are too effective for protection.

Adherents of that theory advocate tear gas or tasers. Come again? They are asking you to handle the situations for which police require shotguns, body armor and superior numbers alone, with only marginally effective tools at your disposal.
Everyone should just learn martial arts.

Most people do not have the time to become very proficient: guns have a much less severe learning curve. Moreover, most martial arts trainers advocate retreat in the face of a knife or another weapon. Fast retreat is least available to the same people who cannot fight with bare hands.
Gun owners can get trigger-happy and blow everyone away.

Psychopaths intent on mass murder can and have used other means, such as gasoline, explosives, knives and garrots. Normal people concerned about concequences of their actions are not likely to kill on a whim. Even a justified homicide (such as to prevent a mugging) would entail legal expenses in excess of $10,000. A wrongful killing would likely land the perpetrator in prison. For these reasons, every gun owner I know is more polite when carrying a firearm; responsibility and restraint are practiced most deliberately.
Banning large capacity magazines will help prevent crime

Murder and drug dealing are already illegal. Can we really expect someone contemplating a shooting spree think “Oh, man! I better not use any magazines over 10 rounds when shooting up that McDonalds…they are illegal”? Just passing another law will not deter the criminally inclined: it will, however, make self-defense less effective. As for the need for large magazines for legitimate self-protection, ask the people who faced mobs of hundreds during the LA riots.
Why would anyone need military-style weapons?

A synonym for “military-style” is “reliable, effective and relatively inexpensive”. Since you have a right to self-defense, you would benefit from access to the most effective tools available.
Women should avoid guns. Assailants would simply take the guns away.

In reality, that does not happen. Guns are not very complicated: it is hard to screw up pointing and hitting the intended target at the distance of a few feet. It is not always necessary to shoot the perpetrator: presenting a credible threat of bodily harm is usually enough to stop an attack.
We should turn the other cheek…

The quote referred to a blow to one’s pride, not a life-threatening assault. Also, most people who would not defend themselves would fight for their child or spouse. Even so, pacifism may be a valid choice for some individuals. Forcing that choice on everyone is neither fair nor realistic.
Why are gun owners so hostile about “reasonable gun control”?

For most gun owners, personal liberty is as much a ethos as Christianity or Judaism, and people who’d confiscate and burn their Bibles/rifles/Torahs elicit a strong emotional response.
Gun control laws seek to make people defenseless in the face of danger, violate property rights and strike at the personal freedom and self-determination. But, as Stalin was fond of saying, “you can’t make progress without breaking a few heads.”