Today the state of South Carolina sued the Justice Department for blocking its new law requiring citizens to show government-issued photo identification to vote. This is just the latest broadside in what promises to be a protracted battle over the constitutionality of state voting laws and federal protections against discrimination.

For decades, Section 5 of the Voting Rights Act has been a cornerstone of civil rights law. The provision requires certain jurisdictions with a history of racial discrimination to get federal “preclearance” before enforcing new voting laws. Today, opponents of the law are trying to dismantle this foundation of our democracy, bringing several court challenges in recent months. They argue that, 50 years after the worst abuses of the Jim Crow era, the law should be struck down as unconstitutional, and that federal protection of minority rights in these jurisdictions is no longer needed. Do they have a point?

To paraphrase William Faulkner, the past is not past.

A quick glance at the wave of suppressive voting laws enacted last year illustrates clearly how important Section 5 continues to be. South Carolina, a state still covered by Section 5, offers an excellent case in point.

If the United States awarded medals for voter suppression, South Carolina would compete for the gold. In the last two years, South Carolina has debated and approved numerous laws that would cripple the ability of minority voters to participate. In applying Section 5 to challenge the voter-identification law, the Justice Department found it could disenfranchise more than 80,000 African-American voters. Twenty-five percent of African American citizens don’t have the requisite government-issued photo identification, compared with eight percent of white citizens.

Laws restricting voting rights threaten to disenfranchise up to 5 million American citizens in 2012.

The South Carolina legislature is now considering a stronger bill that would require would-be voters to present documentary proof of citizenship, such as a passport or birth certificate, in order to register to vote. These documents are hard to procure for many people, such as older African-Americans, who were never given birth certificates because of the racist legal regime under which they were born.

State representatives are also considering a bill—similar to a controversial measure passed in Florida last year—that would restrict individuals and organizations, such as the League of Women Voters, who conduct voter-registration drives. Who would be harmed most? Latino and African-American citizens, who register through voter-registration drives at twice the rate of whites.

Moreover, South Carolina’s crusade has not been limited to legislation. On January 11, in an apparent attempt to justify the new ID law, the state’s Attorney General David Wilson claimed that more than 900 “dead voters” might have participated in recent elections. When pressed to prove the claim, the Attorney General released the names of only six individuals, and it was quickly shown that no voter fraud had occurred in connection with any of them. Governor Nikki Haley has likened federal protection of minority voting rights to a “war on South Carolina” and vowed to “fight hard” against such efforts. Texas Governor Rick Perry echoed this secessionist rhetoric during a presidential debate in South Carolina, proclaiming his state was “under assault” from, and South Carolina was “at war” with, an intrusive federal government.

Governor Perry doth protest too much. Laws such as those proposed and passed in South Carolina, and in numerous other states including Alabama, Florida, Georgia, Mississippi, and Texas—like the literacy tests and poll taxes of an earlier era—may “apply to everyone the same,” as supporters claim, but will systematically suppress the voting strength of minority communities in those states.

South Carolina’s commitment to passing suppressive voting laws shows that Section 5 continues to play a vital role in safeguarding civil rights in the United States. Indeed, the laws recently passed in a number of states constitute the greatest threat to voting rights since the 1960s, threatening to disenfranchise up to 5 million American citizens in 2012, according to a Brennan Center report released in October. Without a check on the ability to abuse voting laws to disenfranchise disfavored groups, bad actors and misguided officials may become even bolder in their suppressive policies. The Voting Rights Act can preserve the rights of the powerless against this threat, but only if it remains in force.