MLK and LBJ's children: Our fathers' vision for voting rights is under attack again

2021 marks the 58th anniversary of the March on Washington.

Martin Luther King, III, is Chairman of the Drum Major Institute, an organization that seeks to inspire individuals to embrace their unique contribution to peace, justice and equity for all. Luci Baines Johnson, the daughter of former President Lyndon Johnson, is a businesswoman, philanthropist and advocate for protecting the rights of all Americans to vote. The opinions expressed in this commentary are their own. View more opinion on CNN.

(CNN)In 1845 James Russell Lowell, the well-known Harvard Law School graduate and abolitionist, wrote words that continue to ring in our hearts over 175 years later. They were written to address national debate over slavery and the impending war with Mexico -- and they are as relevant today as ever.

Once to Every man and nation Comes the moment to Decide
    In the strife of Truth with Falsehood for the good or evil side.
      Some great cause, God's new Messiah, offering the bloom or blight,
        Parts the goats upon the left hand and the sheep upon the right.
        And the choice goes by forever 'twixt that darkness and that light.
          Then to side with truth is noble when we share her wretched crust.
          Ere her cause bring fame and profit. And 'tis prosperous to be just;
          Then it is the brave man chooses while the coward stands aside.
          These were words from a hymn of our childhoods. And they were words that guided our fathers, Martin Luther King Jr. and Lyndon Johnson, in their fervent quests for social justice for all.
          This weekend marks the 58th anniversary of the March on Washington, which in 1963 drew hundreds of thousands to the National Mall to push for passage of the 1964 Civil Rights Act and the Voting Rights Act of 1965. Alas, 58 years later the right to vote is painfully under attack again. Thus on August 28 we must join shoulder to shoulder again at the "March On for Voting Rights" to protect the sacred right of all Americans to have their votes counted.

          My father, the civil rights icon

          As Martin Luther King's son, I saw my family sacrifice countless times because of my father's commitment to the Civil Rights Movement. I witnessed as my father gave his heart, soul and very life for social justice for people of color and for people who felt the sting of economic disadvantage.
          My father died when I was only 10. I cherish the memories of going with him to the YMCA, where he taught us to swim and he could get the physical exercise he sorely needed to sustain his demanding schedule. I remember the father-son times when he made me feel he valued my companionship, as I did his.
          I was orphaned by his sacrifice but inspired forever to do justice in his name and in the names of those who fought along with him.
          I was so young when my father died that I was denied hearing him tell me many of his great stories. I have only learned of them through his life's work. Their value is so important to me that I have embraced them as my own.

          I saw my father, the president, defend civil and voting rights

          As Lyndon Johnson's daughter, I witnessed my father give his political life in defense of civil rights and voting rights. In 1964, as he championed the Civil Rights Act of 1964, I heard him say, "If I lose the South because of my support for civil rights I will gladly do so, because what else is the Presidency for?" I had the privilege of seeing him work with Dr. King, John Lewis, Andrew Young, Ralph Abernathy and countless other civil rights leaders who inspired a whole generation to do the right thing.
          I was there when the 1965 Voting Rights Act became the law of the land. I watched my father give Dr. King a pen used to sign the Voting Rights Act into law. I saw him give another to Republican leader of the Senate Everett Dirksen. I witnessed the bill's bipartisanship. It was a triumphant day when Democrats and Republicans and civil rights leaders all came together to make the right to vote the law of the land for all Americans.
          A month before my father's death, at the LBJ Library's Civil Rights symposium, a very ill Lyndon Johnson ambled up to the stage to make his last public address. I watched him place a nitroglycerin tablet under his tongue and rushed to his side afterwards to ask him why he had come to speak when he was so very ill? He told me "If I had died speaking for civil rights then I would have gone dying for what I lived for. What more could any man want?"

          Taking up where our fathers left off

          Social justice was the cause of our fathers, and now our generation's moment has come. Much of what they accomplished is unraveling, and it is up to us to take up where they left off.
          Voting rights are once again under siege. In 2013, we witnessed the Supreme Court of the United States gut the heart of the 1965 Voting Rights Act. Their 2013 Shelby County v. Holder decision allowed states to circumvent the federal authority embedded in the Voting Rights Act, which had prevented voting changes and redistricting considered to be discriminatory. We have also seen 18 states, including Georgia and Texas -- the home states of our fathers -- fight feverishly to suppress voting, especially among people of color, the elderly and the poor.
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            It is time for all Americans to come together and push for passage of the For the People Act and the John Lewis Voting Rights Act, which would restore the ability of eligible voters to vote free and unfettered. We urge all Americans to implore lawmakers to support these bills and those in their states that make voting easier for registered voters -- not harder. The cause is no less important than it was over a half a century ago. Whenever there is bigotry for some there is loss for every American.
            In 1965, Democrats and Republicans came together to make our fathers' vision for the right to vote a reality for all Americans. Now we must come together once again to deliver on that promise. The anthem of the Civil Rights Movement -- "We Shall Overcome" -- resonates today just as it did a half a century ago. We shall overcome the assault against our most basic and important right as Americans. We must!