There are many reasons why you should learn about bad things that happened in the past.
First of all to educate ourselves and others, let’s take the holocaust for example.
At one point it used to be a required course to graduate from high school, then it became an optional choice, and finally know it is being take out of the whole curriculum.
For those people who are not going to learn about the Holocaust it is going to be hard for them to believe that it actually happened, but if you educate yourself about the things in the past, you can educate others about it so they are not left in the dark!
This is the reason why you should learn about bad things that happened in past even if it was way before you were born!
