As the United States marks the anniversary of Dr. Martin Luther King Jr.’s assassination, the civil rights revolution he helped spur is in peril. The progress African Americans forged has stalled. Will the United States once more turn its back on civil rights?

It has happened before. The first Reconstruction began with the Civil War and ended with the passage of the civil rights amendments ending slavery and guaranteeing equal protection under the law. Newly freed slaves pushed to exercise their rights. They won local elections and served on juries. They helped create what were the first public school systems in the South.

The reaction was brutal. The Ku Klux Klan terrorized African Americans across the South. Democrats became the party of the Confederacy. Barely 15 years later, Reconstruction was abandoned. In the Compromise of 1877, Republicans got Democratic support for ratifying the election of Rutherford B. Hayes to the presidency in exchange for removing federal troops from the South, betraying the newly freed African Americans. As W.E.B. Du Bois wrote, “The slave went free, stood a brief moment in the sun; and then moved back again towards slavery.”

It took a new civil rights and legal movement to end the decades of enforced segregation that followed. In Brown v. Board of Education, the Supreme Court threw out the lie of “separate but equal” and ordered desegregation in public education. In Baker v. Carr, it outlawed discriminatory apportionment schemes. The moral force of King on the outside and President Lyndon Johnson on the inside succeeded in passing the 1964 Civil Rights Act, banning discrimination in public accommodations and guaranteeing equal employment opportunity, as well as and the 1965 Voting Rights Act, enforcing the right to vote. Johnson’s War on Poverty had a dramatic effect on reducing poverty, particularly among African Americans. Whites as well as blacks in the South benefited from King’s revolution.

With the election of Barack Obama, many hailed a new post-racial America. But even with Obama in the White House, stubborn facts raise questions about that optimism. African Americans suffered the most in the Great Recession. The wealth gap between African Americans and whites doubled, with median net worth of African Americans down to a shocking $4,955 (compared to $110,729 for whites). Blacks continue to endure more than twice the rate of unemployment as whites and suffer more long-term unemployment and lower wages, with more than one out of three African American children raised in poverty .

With public education largely funded locally and states and the federal government cutting back, the “savage inequality” of school funding ensures that those schools are not merely separate but also unequal. In our justice system, African Americans are more likely to be stopped by law enforcement, more likely to be arrested if stopped and more likely to be charged and sentenced if arrested. And punitive and discriminatory sentencing, particularly for drug offenses, has resulted in 2.2 million African Americans stripped of the right to vote by felony disenfranchisement laws.

These hard realities are reinforced by political and judicial reaction. Once more, demagogues feed racial paranoia: “In Obama’s America,” preaches Rush Limbaugh, “the white kids now get beat up with the black kids cheering.” Politicians such as Rep. Paul Ryan blame poverty on the poor, claiming that our threadbare safety net – now stripped of aid to dependent children – is turning into a “hammock.”

Efforts to suppress the vote of minorities and the poor are proliferating, with state and after state cutting back voting days, repealing same-day registration and creating strict voter identification requirements to discriminatory effect.

Worse, the five conservatives on the Supreme Court have put civil rights on the retreat. Shelby County v. Holder gutted key parts of the Voting Rights Act. Meredith v. Jefferson Country Board of Education declared affirmative desegregation plans in schools to be unconstitutional. Affirmative action faces continuous assault in the courts.

This retreat is poisonous in our increasingly diverse society. We cannot afford to go back to the confederate way of doing business or politics. We can’t afford to write off another generation of young people of color who will be closer to a majority of our nation when they are adults.

Today, unlike after the Civil War, it will be harder to stop the march of civil rights. Demography will increasingly punish rather than reward the party of white sanctuary. Attorney General Eric H. Holder Jr. has called on states to repeal discriminatory felony disenfranchisement laws. Even a few Republicans have joined with Democrats to try to revive the Voting Rights Act.

But the lesson of Reconstruction is clear: Progress toward greater justice is not inevitable. Equal justice under the law will not be inherited; each generation must fight to extend it or risk watching it erode. We aren’t headed back to the days of Jim Crow, but we have a long way to go before we fulfill the Founders’ promise of equal justice under the law.

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