Fifty years ago this evening, the Rev. Dr. Martin Luther King, Jr. was assassinated. His struggle for civil rights had already made history by that time. But his murder by a white supremacist career criminal became a defining moment for modern America because it highlighted just how important his work was.

Since then, the nation has changed dramatically, and with respect to race relations, mostly for the better. The clearest evidence of this is that no one under the age of 50 today can fathom the society King was working to change. They are puzzled that anyone could have felt and expressed such open hatred and contempt for their fellow man just on the basis of his skin color.