Media playback is unsupported on your device Media caption Inside the mind of White America

The meaning of the term white privilege has evolved over the decades along with the way it is used and by whom, as James Jeffrey explains.

At its simplest level, white privilege is walking into a pharmacy and finding the Band-Aids only match the skin tone of white people. At another level, it's the term increasingly being applied as a political weapon to bash opponents, as Beto O'Rourke, one of the latest to join the race for the Democratic presidential nomination, is learning.

"Beto's bizarre campaign rollout drips with white male privilege, the kind of navel-gazing, self-involved behaviour a woman or person of colour could never get away with," intones a recent advertisement by The Club for Growth, a conservative anti-tax group that supports President Trump's re-election.

The Club for Growth is not alone is accusing Beto of benefiting from having been "born with a blue-blood pedigree, the scion of a prominent family," and having a nigh-on billionaire father-in-law, Bill Sanders (so successful he became known as the "Warren Buffet of real estate").

Beto's mother actually dated Sanders before she met and fell in love with one of his friends, Pat O'Rourke, Beto's father, a politician. Beto has joked about the incongruity of his parents meeting on a date with his wife's father.

On the one hand, this slice of family history offers a good dinner-party tale of serendipity, though it could also serve as a parable of the insularity of the moneyed class that is the source of increasing scorn in America today, fuelling the derogatory application of "white privilege".

Even Beto has spoken of his white privilege after being criticised in the media for his self-indulgence in taking off on a long road trip in the wake of his Texas Senate race defeat to Ted Cruz, leaving his wife looking after their three children.

"Absolutely, as a white man, there is so much privilege built into that," Beto said, while adding he still felt it was necessary for his well being after such a disappointing defeat.

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The exact origin of the terminology "white privilege" is unclear. Before the Civil Rights Act of 1964, "white privilege" was less commonly used but generally referred to legal and systematic advantages given to white people in the US, such as citizenship and the right to buy a house in the neighbourhood of their choice.

But after discrimination persisted for years following the Civil Rights Act, the idea began to gain traction that while privilege was more psychological - a subconscious prejudice compounded by white people's unawareness of holding this power - exerting itself in the everyday advantages that whites experienced.

Peggy McIntosh is often mentioned as having brought the phrase into wider public discourse with her 1988 essay White Privilege: Unpacking the Invisible Knapsack, in which she described it as an invisible force that white people needed to recognise, its manifestations ranging from seeing only your race represented on television, to navigating life without being racially profiled or unfairly stereotyped.

"I find attention to these terms that are born in academia and then become the flavour of the day troubling sometimes, as they can be used in pretty facile and accusatory ways," says Kevin Foster, an educational anthropologist in the African and African Diaspora Studies department at the University of Texas at Austin.

"But, at the same time, by using these terms and concepts, they are getting introduced to more people, sometimes for the first time, so whereas before people might not have had the language to express something they were instinctively aware of for years, now they go: Oh, I get it, that's white privilege!"

Media playback is unsupported on your device Media caption One thing Americans find hard to talk about

But with conservative groups now using the term for political gain - all of Club for Growth's endorsed candidates for 2020 are white men - it begs the question of who gets to make the accusations?

Race doesn't necessarily come into who can call out white privilege, says Foster, who is African American. He notes that just as his being male doesn't mean he should refrain from calling out bad behaviour by other males, a white person can identify an incidence of white privilege by another person and take them to task.

"Privilege is not pejorative, but it should be accounted for," Foster says.

"All power to Beto for going on that road trip after his Senate race, as that sort of thing is exhausting - of course he should have done it if he needed to. If you have access to a vaccine you are not going to not take it because others can't - but, and this is the point, afterwards you should try and ensure it can be extended to others."

The way many people move through society involves a whole intersection of privileges - gender, religion, sexuality, class - some more subtle than others but all of which provide advantages in terms of access to power and resources, says Frances Kendall, author of Understanding White Privilege: Creating Pathways to Authentic Relationships Across Race.

"People know how to use it, but they wouldn't call it privilege - they call it normal life," Kendall says. "Historically, white countries have put at the top of their agendas issues that have greater acceptance."

She says this is one of the reasons she was astonished by the marriage ceremony of Prince Harry and Meghan Markle.

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"It was like a miracle," Kendall says. "Here were all these black people, with gospel singing and a black Episcopal bishop - not exactly a normal sight in an English Anglican church."

In America, the recent college admissions cheating scheme, in which wealthy parents used both economic and social capital to solve a problem - securing their children's admission to elite colleges - served an example of an entitled elite conditioned to get what it wants, with the lengths they were willing to go creating a parody of 21st-century privileges run amok.

"That sort of cynical exercise of privilege is ugly," Foster says. "Though here it was more a case of class privilege - they were all rich."

Beto clearly has class privilege - in addition to his white and male privileges - though almost all politicians have some sort of combination of privileges, and as they must do, Kendall says, if they are to have any chance of succeeding.

This feeds into America's somewhat contradictory relationship with privilege. Its "decision to throw off the British monarchy was accompanied by a new social ethos that rejected privilege on account of birth or family or station," says David Greenburg, a professor of history and journalism at Rutgers University.

At the same time, though, the country has a long history of embracing politicians who came from privilege, including Robert Kennedy, with whom Beto has been compared, and who also ran for the Democratic presidential nomination in 1968.

Image copyright Getty Images Image caption President-elect John F Kennedy stands at the centre of his large family, with brother Robert standing to the right

"No one would have said Bobby Kennedy enjoyed 'white privilege' because the buzz phrase didn't exist then," Greenburg says. "He was born into a family of wealth and influence - that's what privilege properly means. And while some people held it against Bobby - and against Jack Kennedy before him - most Americans look at not where you come from but what you stand for.

"Like Theodore Roosevelt and Franklin Roosevelt, the Kennedys had liberal values. Their policies helped the poor and others who were struggling. Their records in office rebutted allegations that they were servants of their own class interests."

Beto doesn't have a similarly successful record in office to draw on, critics point out. Furthermore, Beto stands among a crowded field of Democratic candidates emerging that includes progressives, women and people of colour. Combined with how privilege is increasingly being reappraised, this all leaves Democrats - and voters - with a decision to make about what Beto represents.

On the one hand, he and his wife are one of the most appealingly modern families in the run for the 2020 presidency: they employ social media to great effect, broadcasting much of their lives in real time, while Beto's propensity for jumping on cafe counters and high-octane energy on the campaign trail has a galvanising impact on crowds wherever he goes (as did Bobby Kennedy).

At the same time, his affluent white traditional family makes it less clear whether he is a vision of the future or a reflection of a past that carries a lot of baggage in the current climate.

"Being a straight white man could be something of a liability for Democratic candidates this time around," political analyst CR Douglas told KUOW, a Washington state outlet. "The energy in the party is with youth, it's with women, it's with minorities."

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But Greenberg notes that while many Democrats may be pleased about the growing racial and ethnic diversity within their party, that doesn't mean they are comfortable about making the likes of skin colour a "litmus test" for a presidential candidate.

The fact is, says Tom Wood, a political scientist at Ohio University, who heralds from Australia, the elasticity that characterises the emergence of political candidates in America is utterly at odds with the way politics works in his homeland and the UK.

"How candidates are selected in the UK usually involves decades of loyal service to the party, be it Labour or the Tories, after which you are offered to run for a safe seat," Wood says. "The American system is amazing in how open it is, and of course it's this element that gave us Donald Trump."

He notes the parallels between the large field of Republican candidates that Trump emerged from in 2016 and the increasing pool of Democratic candidates, and how the latter might throw up another surprise challenger out of left field.

America is the consumerist society, and similarly, voters like to be able to consider their options, though it remains to be seen if and how the "white privilege" factor influences the outcome.

"I admit, when I look at two people, and one of them has been through this and that to get where they are, and the other has done well but had a gilded safety net, then I don't think they have the same credibility," Foster says.

"That doesn't mean I write off the latter, but I do want to know their insights, how they move through the world and account for things they haven't experienced."

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