FORMER US VICE President Joe Biden endured a tough time in the Democratic debate on Thursday night. 

Biden, who’s been leading in the polls for months, is now facing the biggest challenge to his frontrunner status after being forced to defend decisions taken in his 50 years in politics.

On this particular occasion, Biden was challenged on his record on race issues by Senator Kamala Harris. 

Harris took issue with Biden’s record of working with segregationist politicians and his recent trumpeting of that fact.

At a recent fundraiser, Biden mentioned how he’d worked alongside racists in the Senate and said: “At least there was some civility. We got things done.”

Harris called these comments “hurtful” and went further on the offensive by attacking Biden’s record on “bussing”. 

The exchange has become the standout moment of the Democratic campaign so far and has shaped the narrative since. 

Bussing, however, is a term that is very familiar in the United States but may be less familiar here.

So what exactly does it refer to?

Essentially, ‘bussing’ is used to refer to initiatives in the 1970s that took children from predominantly black communities to schools in predominantly white neighbourhoods. White students were also bussed to predominantly black schools. 

The practice was introduced because even though school segregation was officially ended in the 1950s, it was essentially in place due to a lack of opportunity for many African-American children.

Bussing allowed black students to attend better schools in more prosperous neighborhoods and although it was not universally popular it is seen as a key plank of desegregation. 

Harris argued that she benefited from the practice of bussing and her campaign team drove this message home by tweeting a youthful picture of her with that message during the debate.

In her exchange with Biden, Harris accused him of working with those segregationists to “oppose bussing”.

In response, Biden said that this was a “mischaracterisation across the board”.

“I did not oppose bussing in America. What I opposed is bussing ordered by the Department of Education. That’s what I opposed,” Biden said, adding that he was in favour of bussing when a local community supported it.

Harris countered that it is the role of the federal government to intervene when local authorities are not doing enough. 

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In an uneasy exchange after the debate finished, Biden was pushed by an NBC journalist for a defence to Harris’ claims about his record on bussing. 

“It (the federal government) should have a role by breaking down the barriers that exist in institutional racism. That’s what I did when I was a local official and a county official,” he said.

After the debate, Biden’s campaign team sought to bring some clarity to Biden’s position. 

CNN reporter Daniel Dale attempted to break down what they said:

“Biden campaign’s argument is that him saying in the ‘70s that he opposed bussing was understood then to mean he simply opposed federal-mandated bussing, not all bussing. Like when GOP said under Obama they oppose health reform, it was obvious it meant Obamacare, not all health reform,” Dale tweeted.