Black Americans had to fight for their basic human rights.
Black people are a historically disenfranchised people group, and maintaining the truth of their mistreatment might help future generations to be more open-minded and empathic. Lewis's reasoning for telling these difficult stories is if we choose to leave history behind us, not paying close attention to the difficult things, we run the risk of continual mistreatment of minority groups.
The cause of today's systemic injustice is the blatant racism of yesteryear.
Today, it's difficult to find the kind of overt, uncensored racism that was commonplace only 50-60 years ago. That racism was born from American slavery and preserved through a tradition of white supremacy, and even though the racists are now a statistical minority, that doesn't change the fact that the institutions of government and law have been systemically disenfranchising "undesirables" basically the entire time it's been here.
This means that change is necessary, because our past is so blatantly immoral and wrong in regard to the treatment of minority groups—especially black Americans. This can be seen as a support for the ideology of President Obama who called for the continual reforming of society through strategic and intentional change.
Working together, we can solve impossible-seeming problems.
The story depicted in the comic books may be brutal at times, but don't forget, Lewis wrote the works out of celebration for the success of his endeavors, throughout his 60 years of activism. By showing us where we come from, he illustrates how far we've come.
All humans are created equal and deserve equal opportunity and equal representation.
Ironically, America was founded on this principle, but as history proves, sometimes the ideals aren't the reality. The reality was that America's history is rooted in systemic injustice through our dark past of slavery, Jim Crow laws, and continual systemic injustice in the legal system. Just because those things have been tolerated before, they are truly wrong, because every person is valuable, no matter their race or their religion.
