Orwell also wrote, "He who controls the past controls the future. He who controls the present controls the past."
This controlling of the past and future is accomplished by trying to denigrate and destroy people's history and creating an alternate, false history.
An example: Dead White Male slave owners. Another example: Obama's claim that Muslims contributed to America's past. And another: Afrocentrism, which is the claim blacks created civilization, hence Al Sharpton's claim that blacks "were teaching mathematics and astrology before them Greek homos ever got around to it."
It's an attempt to destroy self-esteem and install self-hate, to take away power and give it to use who have done nothing but destroy.
This video illustrates just how important history is to us.