This year’s African-American History Month takes place a half-century after one of the most important years in our nation’s history. On July 2, 1964, after seven weeks of a vicious filibuster by Southern senators, the Civil Rights Act (CRA) was signed into law.

The act had been a major demand of the 1963 March on Washington and was championed by President John F. Kennedy before his assassination. The law ended discrimination on the basis of color, religion, sex and national origin. It outlawed voter literacy tests and desegregated all public accommodations engaged in commercial activity.

Most importantly, the act drove a nail in the coffin of the Plessy v. Ferguson decision of 1896. No longer was “separate but equal” the law of the land. Further, the 1960s period of democratic ferment—preceded, of course, by generations of struggle—also produced the Voting Rights Act and economic justice measures like Medicare, Medicaid and the “War on Poverty.”

These victories did not come easy. During the Senate debate over the CRA, many white and African-American voting rights activists suffered injuries and some even died. Michael Schwerner, James Chaney and Andrew Goodman—three Mississippi Freedom Riders—are among the best known.

Activists of the period also fought bitterly for the right of political representation. In 1964, Fannie Lou Hamer helped found the Mississippi Freedom Democratic Party (MFDP) because segregationists blocked participation of African-Americans in the regular Mississippi Democratic Party.

That summer, just weeks after passage of the CRA, the Democratic Party and President Lyndon Johnson, to appease Southern Democrats, refused to seat the MFDP delegation at the party’s national convention. Fifty years later, our right to the ballot and political representation continues to be thwarted by powerful moneyed interests.

Our nation has a long tradition of undermining and violating its own laws, particularly those intended to give people of color and the poor the full rights of citizenship. But those rights, as Dr. Martin Luther King taught us, are not achievable without greater economic equality.

Less than three weeks before he was gunned down, King told a rally of Memphis sanitation workers, “Now our struggle is for genuine equality, which means economic equality. For we know now that it isn’t enough to integrate lunch counters. What does it profit a man to be able to eat at an integrated lunch counter if he doesn’t have enough money to buy a hamburger?”

King decried the concentration of wealth and power in the hands of a few and the use of that power to deny the rights of working people and the poor. Sadly, that concentration of wealth and power has intensified. This is true not just in our country, but also around the world.

According to a report by Oxfam titled “Working for the Few,” in a world of 7 billion, 85 of the richest people on the planet now have the combined wealth of 3.5 billion, or half of the world’s poorest people. This massive concentration of economic resources in the hands of fewer and fewer people presents a profound threat to democracy, equality and world peace.

We in New York City have thankfully elected a mayor committed to balancing the scales of equality. President Barack Obama also has taken steps to address the issue, such as his plan to raise the minimum wage for federally contracted workers from $7.25 an hour to $10.10 an hour by 2015. That would certainly help, but workers still would have much catching up to do. According to the Economic Center for Policy Research, if the minimum wage had kept up with the increase in worker productivity since the 1960s, today it would be more than $21 an hour.

King reminded us that the arc of history bends toward justice, but it does not bend without our efforts. We must build the unity and the political power necessary to win our just demands for full civil rights, justice, equality and a more perfect union.