Martin Luther King III is a human rights activist.

The massive turnout at Saturday’s march and rally at the Lincoln Memorial, commemorating the 1963 March on Washington and the wonderful spirit of all the participants, was a powerful testament to the enduring dream that my father, Martin Luther King Jr., shared with our nation and the world half a century ago. As we look back on the march, we are called not only to celebrate the legacy of that day but also to address the festering injustices of inequality, racism and poverty in this country.

Although significant progress has been made in some areas, too many Americans have inadequate opportunities to escape poverty, joblessness, discrimination, social neglect and violence.

The date of the ’63 march, Aug. 28, was chosen to commemorate the eighth anniversary of the brutal slaying of 14-year-old Emmett Till. The ensuing outcry helped to awaken a new era of protest against racial injustice. A half-century later, however, African American youth still have good reason to fear racially motivated violence.

When an unarmed 17-year-old walking home with Skittles can be brutally slain by an armed man — a man who had been told by police to leave the boy alone — and that man is acquitted of all charges, something is very wrong. The so-called “stand your ground” and “stop-and-frisk” laws that have been enacted in various states in recent years disproportionately abuse people of color.

These ill-considered laws are a serious threat to the freedom and safety of all Americans. The appalling racial injustice inherent in the Trayvon Martin tragedy reminds us that there is still much to do.

Horrific gun violence in Chicago; Tucson; Aurora, Colo.; Newtown, Conn.; and Oak Creek, Wis., in recent years underscores the dramatic increase in bloodshed in our society over the past half-century, with children slain even in their schools. There is no way we can fulfill the dream of a peaceful society until we enact measured control of deadly weaponry; that includes background checks and a ban on the sale of assault weapons and high-capacity ammunition.

The theme for the 1963 March on Washington, “For Jobs and Freedom,” resonates a half-century later: Unacceptably high rates of joblessness are pervasive. July unemployment figures indicate that the jobless rate for African Americans is 12.6 percent, compared with 6.6 percent for white workers and 9.4 percent for Latino Americans. Discrimination in employment remains a relevant concern.

Fulfilling my father’s dream will also require our society to become one where everyone who wants a job at a decent wage can get one. Reforms are needed to stem the tide of outsourcing good jobs to other nations and to educate and train American workers to meet the challenges of the 21st-century world economy. Doing the latter would also help rebuild our nation. There is no question that a great deal of this country’s infrastructure is in urgent need of upgrade. Millions of Americans of all races are ready and willing to be part of the repair and modernization of our deteriorating roads, bridges, ports and rail systems. In meeting this challenge, millions of jobless people could achieve economic security for their families while helping to build a better America. A stimulus package to upgrade the nation’s infrastructure would surely prove a cost-effective investment in America’s future.

And if we truly want a strong and secure middle class, we must restore the ability of labor unions to organize and represent working people.

Perhaps the most powerful tool we have in the ongoing struggle for jobs and freedom is the ballot box. Since the Supreme Court’s decision in Shelby County v. Holder, an avalanche of voter suppression measures in a number of states has aimed at disenfranchising African Americans, Latino Americans and students. On a deeper level, this is an assault on democracy because it seeks to establish voter suppression as a legitimate and permanent feature of the U.S. political system. Our challenge is to mobilize a new coalition of conscience to restore the Voting Rights Act, strengthen voting rights and broaden voter access in the legislatures of the 50 states.

As I reflect back, I can’t help but ask, what would Dad think? One thing I am certain he would do is work relentlessly to get us all to work together to address today’s most pressing issues.

As I look forward, I can’t help but ask, what is each and every one of us doing to realize the dream of freedom, justice and equality for all?