Although I am a strong advocate for it, let's forget the 2nd Amendment just for a moment. It's purpose was for the people of this nation to be able to defend themselves against all enemies, foreign and domestic. The ide of it dates back to the Roman Empire or earlier and seeded by the Revolutionary War when George Washington commanded an ill-prepared, untrained army against the British.
Though modern history still proves that even elected leaders can turn armies against their own people en masse, keeping relevant the very purpose of the 2nd Amendment, the threat of of internal or external governmental forces is not the source of current dialog. It is ourselves. Crimes by citizens against citizens.
The right of self defense is not an enumerated right per se. It's not mentioned in the 2nd Amendment. It's a natural right coming from the instinct we have toward self preservation. Fight or flight, when threatened. Specifically mention in the Declaration of Independence is the right to life, liberty and the pursuit of happiness. There should be no argument that no right can exist without the right to defend them.
With that brings the right of self defense. It we have the right to life and liberty we must also have the right to defend them. There have always been evil men with evil intentions long before guns. Guns weren't invented to level the playing field, they were invented to gain the upper hand. It that regard it doesn't matter if you're talking about defending a nation with standing armies, or defending yourself. In self defense, you don't fight fair, you fight to win.
Most modern hand guns and even 'assault rifles' are not efficient killers. That is not the point of self defense, nor of using guns for self defense. Of one attacked me and I defended myself with a baseball bat, assuming I was the victor he's probably more likely to die or suffer permanent injury than if I had used a gun. The distinct advantage of the gun is to allow the defender to create distance to prevent an attacker from carrying out his act while maintaining the ability to stop the threat. Anyone with combat training will tell you if you get into a knife fight, you're almost guaranteed to get cut, and likely severely. Even having a knife to defend yourself with still means you have to put yourself within reach of the attacker. Any weapon short of a projectile weapon puts you in physical contact with an attacker subjecting the ability to stop said attack to size, strength and condition of the defender.
Defending my life is MY right and no law requires me to be on a level playing field when self defense is righteous.
But self defense is not only an individual right, it's an individual responsibility. This is not to say you are in any way REQUIRED to defend yourself, but rather it is no one elses' responsibility. No one, not even police officers, have a duty defend your life. When they do, they do so only after they've determined they can do it with minimal risk to themselves. Those that act selflessly and put themselves in harms way are said to go OVER and ABOVE the call of duty.
Limiting access to guns, magazine capacities, or the right to carry said weapon, ONLY assures a would be victim LESS capacity to stop a potential threat. Force me to defend myself with anything else and it greatly increases the odds of me being a victim, even if I'm the victor.