President Obama wrote a response to a NewYork Times article on how Republicans have tried to dismantle the Voting Rights Act of 1965.
The op-ed takes a look at how American Conservatives used tactics like literacy tests to suppress the vote of African Americans after the Civil War (especially in the South). It then talks about how over the past 50 years Republicans have pushed to dismantle key parts of the Voting Rights Act that protects the vote of African Americans. Things like the Voter ID laws are only allowed because key provisions of the Voting Rights Act have been dismantled.
You can read the whole op-ed here.