Obama and Hillary have already confused this issue, again, over the club shooting.
Do you really think 50 people would be dead if those who desired to were packing concealed weapons that evening? I can't say if accidental crossfires or people shooting themselves wouldn't have happened, but I guarandamntee you that there wouldn't be near as many dead.
And its easy not to shoot yourself with any weapon. Just dont point it at any part of your body while pulling the trigger. They require user input to operate in case you didn't know.
Guns dont kill people. People who dont value human life kill people.
People with guns kill people. Do you think that he could have been so destructive with a baseball bat? But then again, he could have driven a car into the club and maybe done much worse. So your dumb "only people kill people" is true in some sense but not the one you intended. A person with a weapon kills people. Guns are very easy to use and carry so people use guns to kill people. The two are connected.
Guns are a common instrument in suicide. The probability of a person intentionally killing himself with his gun is tens of times more likely than ever using one to defend. Also guns are tens of times more likely to harm a person close to the gun owner either by accident or intentionally in a criminal act than to be used in defense. Finally, guns are more likely to be used to kill another by a fearful person who would not have done so and nobody would have been hurt than to be used in legitimate defense. The popcorn killer* in a theater in Florida is one example. There are many other examples that I can cite but that would be boring. At the bottom of a very long list of instances where a gun injured or killed another is the case of legitimate defense. Of all the times a gun is used to kill or injure somebody the percentage of those instances that are legitimate defense is 0.8%, or less than 1 time per hundred dead or injured by a gun.
Fortunately, your idea of everybody -- every man woman and child -- carrying a gun is hypothetical. It it were actually true, we'd have mayhem. The numbers of accidents and criminal uses of guns on people would be so large as to become an epidemic. The cases of legitimate defense would be still be tiny. To arm the populace for the rare instance of defense is truly insane.
That said, I don't think the problems of random mass murders is large enough to justify draconian gun control laws. Again, its a tiny risk and not worth the police actions required to eliminate semiautomatic rifles from the gun owner world.
*
https://endstandyourground.wordpress.com/2015/12/28/florida-theater-shooting-stand-your-ground/