History teaches us nothing but biography of murderers

Almost all human history is war. In schools we learn mostly about battles and power-hungry warlords/generals. I believe that it is a huge waste of time to memorize the dates on which large groups of people were slaughtered.

Humanity has never seen long periods of peace until now. Most of our ancestors failed miserably in creating a peaceful world. Should we still make these people our heroes? Is it a good idea to put them on a pedestal as an example of success? Is it not yet the time to try to sever the link to our brutal, violent animalistic past and condemn it for what it is?

Wouldn't it be better to shift teaching towards the history of scientists, inventors and artists?