I think we exhaustively discussed this about a year ago.
the ultimate consensus is that one should only own a gun if one is properly trained in gun use. With added power comes added responsibility.
There are so many cases where an untrained person has discharged a gun in self-defense, and has missed the perpetrator and has killed a child, wife, neighbor or bystander. You would then have to live the rest of your life with the burden of guilt. This is particularly likely to happen if you live in an apartment building.
Shooting a gun is not at all like it is portrayed on TV. It’s not just point and shoot.
Also, if you have children, you must take steps to make sure that the children never, ever, ever can get access to the gun. You must lock it in a special safe made for guns and have a trigger lock. We have all heard what can happen when a child finds a hidden gun.
If you are willing to take the training and buy all the safety equipment, then you may consider a gun, if you need one.
Why do you need one?
(note: I am not against gun ownership, I am against naive and untrained gun ownership)