Conservative Bruce Barlett is one of those that has been quick to blame the ideology for the oppression of African Americans from the Civil War to the Civil Rights Act:
The libertarian philosophy of Rand Paul and the Supreme Court of the 1880s and 1890s gave us almost 100 years of segregation, white supremacy, lynchings, chain gangs, the KKK, and discrimination of African Americans for no other reason except their skin color. The gains made by the former slaves in the years after the Civil War were completely reversed once the Supreme Court effectively prevented the federal government from protecting them. Thus we have a perfect test of the libertarian philosophy and an indisputable conclusion: it didn't work. Freedom did not lead to a decline in racism; it only got worse.
Now, on the surface, I can see some of my liberal friends nod in agreement. But the fact is, the years of Jim Crow were not the result of libertarianism, but state-sponsored racism. In short, Jim Crow came from the government, in this case, the state government. State after state created laws that seprated the races and gave African American children a sub-standard education. Bartlett is correct that the federal goverment expanded rights to include African Americans. It's an example of why many on the right are wary of government: it is powerful enough to both expand and retract rights. Case point: the internment of 100,000 Japanese Americans during World War II, something that was done by the federal government.
David Bernstein offers a pretty good explaination of the post-Civil War era and how it was anything but libertarian in regards to civil rights. He goes after Bartlett with these words:
...for Bartlett to attack libertarianism with the premise that American law was libertarian with regard to how blacks were treated in the Jim Crow South, when in fact they suffered from overt government discrimination, blatantly discriminatory Jim Crow laws, private violence acquiesced to by the government (and sometimes with the participation of the government), and a denial of voting rights based on race, is just risible.
The fact of the matter is, racism has been deeply woven into all sectors of American society. No institution, no ideology was left unscathed. (Conor Friedersdorf has an excellent post -using material from Barlett, no less, about how some heroes of the left thought about minorities way back when.)Government, especially the federal government, has done a fair share to help African Americans and other minorities in America, but it has also done a lot of harm to those communities as well. That is one of the reasons racial discrimination persisted. The fact that government, state and federal, is no longer able to participate or give its blessing to racism has paved the way for African Americans to have greater participation in American society. It's why we now have an African American president. Now that's libertarian.