Many Americans are stunned by the recent pipe bombs mailed to President Donald Trump’s critics and by the 11 murders of Jews at the synagogue in Pittsburgh. The hateful social media posts by the accused men have caused no small amount of introspection for many Americans.Many elected officials have opined that “we are better than this as a nation” and that “this is not who we are.”I disagree. We have a long history of such violence. It is quintessentially who we are.As a black man born in Fort Lauderdale in 1945, having come of age during Jim Crow’s racist “separate-but-equal” era, I know that Americans are capable of unspeakable atrocities.Some of these atrocities are violent, while others are social, psychological and economic practices that have the power to determine the very quality of our lives.While the United States polices and judges the human rights behavior of other nations, we are hardly the exemplar of valuing human worth and dignity. The old instinct to discount and dehumanize non-whites remains at the core of the American character.Consider the shameful history of how blacks have been treated. We were brought to the colonies in the holds of ships in 1619 as slaves. We were not officially given full citizenship until 1865, with passage of the 13th Amendment. Many whites, mostly Southerners, immediately sought to dismantle black citizenship by suppressing our ability to vote. Without the vote, second-class citizenship was, and is, assured.I remember as a kid that almost every facet of life was stacked against us. We were powerless to do anything about our under-financed and poorly equipped “Negro schools.” Home loan rejections and auto loan discrimination were a given. We could not enter certain buildings or swim in designated areas of public beaches. Black mothers could not give birth at local hospitals.I learned at a young age that persistent injustice is never arbitrary. It is organized to harm specific people.I recall the evening in July 1959, when my mother, father and I drove to the Greyhound Bus station in Fort Lauderdale to pick up three of my young cousins from Virginia.They had not come for summer vacation. The public schools in Prince Edward County where my cousins were students had been shuttered. Whites would not let their children attend school with blacks. A few black churches opened their doors and used untrained teachers. Some kids, like my cousins, found schools out of state where relatives lived.Whites used the tax dollars from the school closures to establish private segregation academies for white children. In 1964, the courts overturned the policy, and public schools reopened to everyone. By then, however, severe damage had been done. Research shows the illiteracy rate of blacks in Prince Edward County ages 5 to 22 went from 3 percent to 23 percent.This kind of inhumanity, although it did not involve guns, ruined many lives forever.When I first heard about the Pittsburgh shootings, I was reminded again that violence is a way of life in America.I immediately thought of historically black Emanuel A.M.E Church in Charleston, S.C., where, in 2015, white racist Dylan Roof gunned down nine African-Americans even as some invited him to worship with them.I also thought of the 1963 bombing of the 16th Street Baptist Church in Birmingham. KKK members killed four black girls with dynamite. The girls were preparing for Sunday morning services.The heinousness of the Pittsburgh synagogue murders also reminded me of Harry and Harriette Moore of Mims, Harry was an outspoken educator and president of the Florida chapter of the NAACP. His activism for black teachers angered local whites. On Christmas night in 1951, when the couple had gone to bed after celebrating their 25th wedding anniversary, a bomb planted by the KKK blew up their house. Harry died en route to the black hospital in Sanford. Harriette died nine days later in that black hospital.Hate-inspired practices and tragedies will continue. They may be increasing. Despite what politicians and others claim, this is who we are as a people.