Prince Harry and Meghan Markle, the Duke and Duchess of Sussex, appear to have embarked on a new course in recent weeks as they seek to define their lives in America by adding political issues and influence into their established interests of being royal humanitarians embracing US celebrity norms of wealth, fame and talkshows.

First it was Meghan, cold-calling two Republican US senators – West Virginia’s Shelley Moore Capito and Susan Collins of Maine – to urge them to support paid family leave provisions in Joe Biden’s languishing Build Back Better legislation.

“She called me on my private line and she introduced herself as the Duchess of Sussex, which is kind of ironic,” Collins told Politico. Collins added – perhaps a little disappointingly for fans of the royals – that she herself was “more interested in what the people of Maine are telling me” than members of British royalty.

Meghan then appeared at a New York Times forum to press the issue. “This is one of those issues that is not red or blue,” she said, underscoring an earlier Paid Leave for All letter in which she stressed that she was “not an elected official, and I’m not a politician”. She was, she wrote, “an engaged citizen and a parent”.

The targets of her letter? The Democrat bigwigs Nancy Pelosi, the House speaker, and the Senate majority leader, Chuck Schumer. She has also reached out to the New York senator Kirsten Gillibrand to offer her help around paid leave campaigning.

Her husband, Harry, has also taken his turn, informing a panel at a tech forum last week that he had warned the Twitter CEO, Jack Dorsey, that “his platform was allowing a coup to be staged” a day before the attack on the Capitol on 6 January by a Trump-supporting mob. By midweek the couple were back on familiar ground, paying tribute to armed forces on Veterans Day and helping to raise awareness of returning veterans’ mental health.

For some observers it is a clear effort by the Sussexes to get – at least partially – involved with the politics of the country they are making home. And, given the fractious nature of US politics, that is not an easy path to tread.

“They’re trying to rebrand themselves without completely rejecting the royal moniker,” says Arianne Chernock, a professor of history at Boston University and author of The Right to Rule and the Rights of Women: Queen Victoria and the Women’s Movement. “Meghan is adamant that hers is a human rights issue that she as an American can speak to, but the issue that she casts as non-political unfortunately plays out in the US context as a very partisan one.”

The process of disentangling from royalty while still benefiting from the insider advantages it confers is also a delicate tightrope. But American fascination with Meghan “is fuelled by her open embrace of her identity and her attempts to connect it to a multiracial, multicultural global population”, says Chernock.

After the Oprah sit-down interview in which the pair criticized the royal family and spoke of the racism they had faced, anEconomist/YouGov poll showed that about 40% of American adults overall feel personal sympathy for the couple, and were twice as likely to sympathize with the couple than with the royal family.

But such sympathies are not entirely organic. The Sussexes’ quest to define their new lives in the US is plotted out. Last week, a witness statement released by the court of appeal in London that stemmed from a libel case Markle won against the Daily Mail showed that a recent coming-to-America account, Finding Freedom, was not unauthorized, as the couple had claimed, but cooperatively scripted.

The revelation led some to wonder where the recent forays into the US political realm are headed.

Until now, the US republic’s relationship with foreign royalty, or in this case fringe royalty, has followed relatively clear lines, as framed by the constitution to prevent a society of nobility from being established in the United States.

“People use titles all the time in America but they can’t use them for any actual purpose,” says David Hackett Fischer, author Albion’s Seed: Four British Folkways in America, a classic study in how four groups – Puritans, Royalist Cavaliers, Quakers and borderland Scots-English – came to shape the culture of the regions they settled.

“There aren’t many royalists among my fellow citizens, but they may be intrigued by people with a title,” Fischer says, “and most Americans have absolutely no interest in aristocracy or monarchy and don’t think it should have any standing.”

But celebrity is a different matter.

“Americans don’t think of celebrity as an order, but celebrate individuals by their interest in them – as film stars, athletes, or whatever they may be, and some because they have a lot of money.”

The Sussexes, he says, “are celebrities only in the sense that the tabloids cover them, but that’s about the only thing that flows from their status”.

But the relative acceptance within some Democratic circles of Meghan’s political input suggests more than shared causes in a tense political moment. “Rightly or wrongly, she can do things average citizens can’t,” says Bruce Freed at the Center for Political Accountability. “It’s star power. It feeds the ego to get a call from a prominent person.”

Certainly Gillibrand appeared impressed. “I could hear how sincere she was about advocacy,” Gillibrand told the 19th website after her chat with the duchess.

Still, the couple are fairly far advanced in their royal-to-celebrity transformation.

The outgoing New York city mayor, Bill de Blasio, in September gave the couple a tour of the World Trade Center before the Sussexes headed off to another big-stage fundraiser, the Global Citizen Festival, themed to pressure western nations to donate 1bn vaccines to developing nations.

As one well-placed Hollywood society power-broker remarks, “why stay in Britain as a walk-on, or a crowd-scene to provide atmosphere, when you can have starring roles in America?”

And they certainly have powerful friends easing their way. The couple’s progress in the US has been smoothed by Nicole Avant, President Barack Obama’s ambassador to the Bahamas, a Montecito neighbor and wife of Hollywood’s most powerful executive, the Netflix CEO, Ted Sarandos. They may also count on Mellody Hobson, Meghan’s co-panelist last week, president and co-CEO of Ariel Investments, the chairwoman of Starbucks, and wife of the Star Wars director George Lucas.

But some steps are discernibly precarious.

Last week, per reports, the couple faced criticism that their lucrative Netflix deal is at odds with the streaming platform’s hit The Crown that will, in its fifth season, depict Harry’s mother during the years of her controversial Panorama interview and subsequent divorce.

As yet their Netflix production account reveals little specific direction beyond saying its mission is “making inspirational family programming is also important to us” and “to share impactful content that unlocks action”.

All of which points to an effort to fashion a new brand-identity despite the contradictions of complaining about press scrutiny and then going to Hollywood to actively court it.

But in many ways, the Sussexes’ attempt to cast their activism within a humanitarian framework is in keeping with all members of the royal family who have made their relevance turn on humanitarian pursuits since the 18th century.

“It’s one of the pitches they make for continuing relevance, and one way that they use to justify their power and privilege,” Chernock points out.