Whenever I see American houses like this one, it inevitably reminds me of how low their security is. That door for instance, would not live up to the standards for taking out a home insurance in Sweden.
An average Swedish door is supposed to withstand violent attacks (from for example an axe, or a chainsaw) for several minutes without breaching. That mainly applies to apartments though, whilst houses often have a little bit lower security standards, I can admit.
Using The Second Amendment as a way of feeling safe really isn't about safety. It's more a question of who is quick to shoot first.
And to put up a very simple moral lesson here: if you kill someone, regardless of circumstances, you still need to live with it for the rest of your life. Even if it just is in self defence, you are still a murderer. It's very simple really. If you want to, we can also make a reference to the Bible regarding killing.