Martin Luther King Day was signed into law by Ronald Reagan in 1983 and first observed in 1986. Either in the spirit of nonviolent protest encouraged by Dr. King or in the spirit of political partisanship (depending on your point of view), many political and religious leader challenged the establishment of the federal holiday. Even Reagan was against it before he was for it.
Any great leader, precisely because she or he is great, has a mixed legacy, precisely because great leadership requires tough, unpopular, stands on important questions. I would like to think few would nowadays openly challenge Dr. King’s efforts to desegregate public transportation in Birmingham Alabama in 1955, for example. But many still challenge his stand against corporate capitalism.