What is the point of teaching history in schools?

I am not really sure what is the point of teaching history in school to young kids - is it because we want them to learn from their (and others) mistakes or are we teaching them effective ways of messing things up? Take the British policy of Divide and Conquer - we now recognize that as a tactic by the British to create disharmony in India and benefit from it at the expense of so many lives the after effects of which still leeches at Pakistan and India's soul. What do we want the kids to learn? that divide and conquer is a bad thing and must be resisted at all costs to prevent disunity or that it is really effective policy that hampers the growth of countries for multiple lifetimes? 

What is the face we are presenting to the younger generation: Life is too short for regrets or is Life too long for having no regrets.

- thoughts swimming in my head this morning after reading Justice Katju's case for reunification: http://justicekatju.blogspot.in/2012/12/a-case-for-reunification-of-india-and.html