Georgetown University Professor Michael Eric Dyson lashed out at conservative strategist Mary Matalin, a former aide to Vice President Dick Cheney, after she defended her one-time boss for branding Nelson Mandela a terrorist in the 1980s.

Following Mandela's death last week, several media outlets pointed out that Cheney had not only voted against sanctions on South Africa's apartheid government, but had also maintained that he didn't have "any problems" with the vote as late as 2000.

On ABC's This Week, Dyson observed that "conservatives get a little bit of amnesia when they forget that Dick Cheney wanted to put him on the terrorist list and insisted that he stayed there, that Ronald Reagan resisted -- he said on the one hand that Nelson Mandela should be released, but he depended upon a white supremacist government to reform itself within."

"When will you ever get tired of beating up on Darth Vader, who said Nelson Mandela is a good man," Matalin shot back, referring to Cheney. "It was a complicated situation, the ANC was a terrorist organization at one point. He has since said wonderful things about Nelson Mandela."

"But when you say about excusing Darth Vader, so to speak, this is not just about rhetoric," Dyson insisted to the former Cheney aide. "This is about public policy that prevented the flourishing of ANC, and look, when they had the feet on the neck of Nelson Mandela and millions of black people in South Africa."