The white policeman stands in the center of the photograph, the German shepherd’s leash wound loosely around his left hand. With the right, the officer is reaching out to grab the cardigan of the young black high school studentdrawing him closer to the dog snapping viciously at his waist. The teenager’s eyes are cast down, a living symbol of nonviolence, his knee thrust forward as if to block the attack. Behind him on the street, other African Americans look on with alarm.

The Associated Press photo, taken on May 3, 1963, as Eugene “Bull” Connor’s Birmingham, Ala., police force trained water hoses and snarling dogs on peaceful civil rights protesters, startled and shamed white newspaper readers across the country.

“The image of the savage attack struck like lightning in the American mind,” civil rights historian Taylor Branch wrote. Though in recent years some have disputed the intentions of the officer in the photo, the impact of the picture was immense.

Two days after it was published, President John F. Kennedy fumed in frustration at the photograph splashed above the fold on the front page of the New York Times and declared civil rights “a national crisis.”

The image symbolized the brutality of American racism, so it resonated deeply when President Trump conjured it Saturday to warn crowds protesting the death of George Floyd, the 46-year-old black man who died after a white Minneapolis police officer pressed a knee into his neck.

If protesters had attempted to breach the White House fence Friday, Trump tweeted, “they would have been greeted with the most vicious dogs, and most ominous weapons, I have ever seen. That’s when people would have been really badly hurt, at least.”

The remarks were met with outrage in many quarters, and a scathing reply from D.C. Mayor Muriel E. Bowser (D), who said the president had “glorified violence” by recalling some of the worst images in civil rights history.

“I’m not sure to what degree Trump even knows the history about this. I doubt that he knows that much,” said Tyler D. Parry, assistant professor of African American and African diaspora studies at the University of Nevada in Las Vegas “But you don’t even have to be an expert to know that threatening protesters with vicious dogs evokes a very uncomfortable and heinous chapter in American history.“

In fact, many chapters, stretching centuries back, said Parry, who has researched the topic extensively. Dogs were employed as instruments of terror against black people long before the civil rights movement, beginning with their use aboard slave ships, he said, and are still used disproportionately by police against African Americans today.

During slavery, the now-extinct Cuban mastiff, or Cuban bloodhound, known for its ferocity and powerful jaw, was favored by many slaveholders for catching escaped slaves. Because of long-debunked racist theories, owners believed African American bodies emitted a scent that was distinct from that of whites and trained their dogs for the hunt by having them chase and tree black men.

The fright instilled by slave-catching canines — known in the trade as “Negro dogs” — figures prominently in the narratives of enslaved people. “Plenty times de [slaves] run ‘way, cause ‘dey have to work awful hard and de sun awful hot,” reads a 1936 narrative of an ex-slave by the Federal Writers’ Project. “Dey hides in de woods and Mr. Snow keep [slave] dogs to hunt ‘em with. Dem dogs have big ears and dey so bad I never fools ‘round dem. Mr. Snow take of dere chains to git de scent … and dey kep’ on till dey finds him, and sometimes dey hurt him. I knows dey tore de meat off one dem field hands.”

Dogs remained tools of racial oppression through the Jim Crow era. As African Americans were imprisoned in increasing numbers, often unjustifiably to provide penal labor, hounds were used to hunt down escaped inmates, who would try to throw the dogs off their tracks by sprinkling cayenne pepper or garlic in their wakes. The threat posed by dogs became such a part of black life that it was immortalized in song and verse. Nina Simone crooned about “hound dogs on my trail” in “Mississippi Goddam,” Parry notes, and poet Margaret Walker described police “Straining their leashed and fiercely hungry dogs.”

Dogs were often brought to lynchings to intimidate and brutalize black victims. Before the advent of the first police K-9 units in the 1950s, police held public exhibitions in which dogs raced to track down black men The fastest to do so were declared ready for sale, said Parry, who has written about the role of dogs in maintaining racist systems from slavery forward.

Well before Connor let loose the German shepherds in Kelly Ingram Park, canines were being deployed against black people throughout the South. In fact, in his pursuit of the fiercest K-9 force around, the Birmingham commissioner of public safety had scoured the region for the best candidates available. Two years before the iconic Birmingham photograph was shot, Greenwood, Miss., was a hot spot for K-9 attacks against black residents.

“A lot of these attacks were occurring before Birmingham,” Parry said. “It’s just that Birmingham got national attention and the images were disseminated.”

Martin Luther King Jr. and Malcolm X even debated how protesters should respond to the canine threat. “If a dog is biting a black man … then that black man should kill that dog or any two-legged dog who [sics] the dog on him,” Malcom X once said. King sympathized with activists’ fears but argued against bringing knives to protests for the purpose of killing attacking dogs.

“The reality for black people in the United States is that white people have often sympathized more with animals than they have with black people,” Parry said. King believed “if there were videos or photos of black people stabbing police dogs … that that would create less sympathy for the protests.”

Connor’s intentional cruelty has parallels today. In some U.S. cities, African Americans are still terrorized by officers with dogs, just as they are disproportionately pulled over and killed by police.

So quick were officers in the Los Angeles Police Department to sic dogs on people of color — referring at one point to black youths as “dog biscuits” — that the department’s practices were challenged in 1991 by several civil rights groups before the lawsuit was settled amid promises of reform. As recently as 2013, research by the Police Assessment Resource Center showed a troublingly high number of African American and Latino residents of Los Angeles had been bitten by police dogs.

Two years later, the Justice Department investigation into the Ferguson, Mo., police department following the 2014 shooting death of Michael Brown revealed that “in every canine bite incident for which racial information is available, the person bitten was African American.”

Ferguson police officers “command dogs to apprehend by biting even when multiple officers are present,” the report concluded. “They make no attempt to slow situations down, creating time to resolve the situation with lesser force. They appear to use canines not to counter a physical threat but to inflict punishment.”

So it hardly matters how much history Trump actually knows, Parry argues, given the evidence extending back centuries.

“What we’re seeing with what the president is saying, is that things are not terribly different in 2020,” Parry said. “He is embedded in a system that considers this normal.”

Correction: An earlier Associated Press caption on the photograph with this story incorrectly identified the African American teen as a civil rights protester. In fact, high school student Walter Gadsden was not a protester but a passerby, according to information that has surfaced in recent years. After a Washington Post inquiry, the Associated Press changed its caption. This version has been updated to included the new caption.The story has also been updated to refer to the teen as high school student.

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