While I agree that many members of the Civil Rights movement have devolved into demagogues, I take exception with the notion that the Martin Luther King did more harm than good.
His I have a Dream speech was one of the great moments in American history. The fact that the man was flawed does not change that.
The Republican party was founded in part as the antislavery party and following the Civil War it was difficult to find a black American who did not support the Republican party.
So, what happened?
The first Ku Klux Klan founded in Tennessee in 1865 was rabidly antiRepublican. In fact in 1868 they claimed to have murdered 1300 Republicans. In 1871 US Grant got the Grant Civil Rights Act, also known as the KKK Act, passed to put an end to its influence.
The Hayes Compromise of 1876 was meant to bring the North and South together, but in fact it costs blacks many of the gains they had made and left them feeling abandoned.
The KKK did lose influence until The Birth of a Nation released in 1915 portrayed the organization as the defender of white womanhood and moral values.
The MSM strikes again and the second KKK was born, not a nation.
The second KKK gained most of its influence in the North among Repbulicans where it developed an antisemitic, antiCatholic, antiimmigrant and of course racist philosophy. It reached its peak in 1924 when Klansman Edward Jackson ran as a Republican and won the Governorship in Indiana. In 1926, the Grand Dragon D.C. Stephenson would be convicted of rape and murder. The scandal would do irreparable damage to the Klan. But the attitudes remained.
Lyndon Johnson could not have passed the Civil Rights Act of 1964 without Congressional Republicans and yet Barry Goldwater, the Republican nominee was an opponent of the legislation.
I think the Republicans lost the support of black Americans because they were divided at their base. Divided between conservatives who were believers in states rights and suspicious of black activism in particular and change in general which made them vulnerable to the rhetoric of the Klan... and their true self.
Their true self was the reformer who believes in government by the people, for the people. This division is the reason the Democrats got credit for finishing what the Republicans started.
Ken Mehlman said as much in a recent address to the NAACP. He said "We were wrong".
Now conservatives can either accept that and learn from it or they can attack a black preacher who was shot by a white supremist.