1) Guns are a form of protection. Shields, armour and helmets protect you. Guns shoot toxic pieces of lead into other people.

And nukes only bake your opponents into radioactive dust while their house falls on them, yet the US and Europe arguably exist in their present form because we had enough nukes to make the USSR avoid direct conflict. Guns raise the stakes to death, and by doing so they deter assault.

2) Guns are a form of self-defence. They can be, sure. However, statistically speaking, more guns are used in crimes than are used in self-defence. A study of gun use in the 1990s, by David Hemenway at the Harvard Injury Control Research Center, found that criminal use of guns is far more common than self-defense use of guns.

Your link is not to his study. Let me guess, he defined "use" as actually shooting someone? Astonishingly, brandishing a firearm can make a potential assailant flee, your study actively sought to come up with numbers to justify its conclusion, thats shitty research present in most gun studies.

3) I don't trust the government. If the government wants to get you, then your Dirty Harry handgun is not going to stop them. End of story.

Common leftist trope. My rifle will not protect me from the government, which has a large and mobile force that they will move around to outnumber any given individual. However, it will:

1. Enable me to join a lessor force that fights a long slow guerrilla war in an effort to change the governments activities.
2. Enable me to take a couple of the agents sent to unjustifiably attack me, with me, thus preventing mass incidents of similar actions through attrition of government forces. As Aleksandr Solzhenitsyn wrote in Gulag Archipelago.

What would things have been like if every Security operative, when he went out at night to make an arrest, had been uncertain whether he would return alive and had to say good-bye to his family? Or if, during periods of mass arrests, as for example in Leningrad, when they arrested a quarter of the entire city, people had not simply sat there in their lairs, paling with terror at every bang of the downstairs door and at every step on the staircase, but had understood they had nothing left to lose and had boldly set up in the downstairs hall an ambush of half a dozen people with axes, hammers, polkers, or whatever else was at hand?

Authority abuses power, and armed populace is a limit to that abuse. This is why grandfathering in previously owned guns during bans does not mollify gun owners, we are not here to protect OUR guns, we are here to protect the right as a limitation on government power.

I would add that guns will enable to 3. Do ANYTHING more useful than throwing rocks at tanks.

4) A 100 lb woman shouldn't have to struggle with a 300 lb rapist.

But you can't arm the victim without simultaneously arming the rapist. So, instead of a rape occurring, which is consequently then investigated by the people whose job it is to investigate rapes, you have a bloodbath. Maybe the rapist gets killed, maybe the victim gets killed, maybe they both get killed, or maybe innocent bystanders get killed.

And every woman gets to decide for herself if she would rather run the risk of being attacked by a casual rapist who will let her live instead of one who will kill her after raping her, or take the risk of meeting an armed rapist and losing the fight.

More importantly, why do you assume a gunfight? When a criminal sees a gun, they regularly flee, they know civilians cannot legally shoot them in the back but will shoot them in the face. They usually run away and try to find a different victim, this one is too prepared for them.

There are alternative ways to deal with rapists which are final, much safer, and do not end in loss of life.

Hrm, like blowing a whistle?

5) Guns don't kill people. People kill people.

Then it is a stupid idea to give them guns then, isn't it? Unless you are trying to make fucking sure.

It is a rather silly slogan with nuanced meaning. It means that guns are tools, responsibility for and causes of violence are human. Nobody sane picks up a gun and says "Welp, I have a gun, guess I should go kill someone" Stop crime by trying to locate the causes of crime, rather than merely disarm people.