The Rev. Dr Martin Luther King as so important because he came to symbolise the Civil Rights movement. He did not invent it, and he was not the only leader in it - but he captured the public imagination more than anyone else. Such things as the “I Have A Dream” speech may have been taken (almost word for word) from other Civil Rights speakers (just as his doctoral thesis was actually the work of another person) - but it was the way he delivered a speech and the time-and-place that was important. In the 1960s if people had heard of only one Civil Rights leader it was Martin Luther King. Without in any way being insulting , he was a “showman” - and it was GOOD that he was a showman. A quiet academic theologian would not have got any public attention or been able to inspire a mass movement.
Yes his private conduct left a lot to be desired (and which of us is without sin?) and his political opinions tended to go into some strange places in the 1960s - but the basic point remains. Was Segregation a great moral evil? Yes it was. Who did more than any other person to campaign against it? To turn the public against it? Martin Luther King was that person.
