Could Trump strip citizenship from Elon Musk, Zohran Mamdani or Rosie O'Donnell?

CNN

18-07-2025

What do the world's richest man, a candidate for New York City's top job and a comedian who once co-hosted 'The View' have in common?
In recent weeks, President Donald Trump has made comments implying their US citizenship could be in jeopardy.
Trump told reporters he'd look into the possibility of deporting Elon Musk. He threatened to arrest Zohran Mamdani. And he posted on social media that he's seriously considering revoking Rosie O'Donnell's citizenship.
The comments come as his administration is also sharing broader plans to prioritize denaturalization, the legal process used to strip individuals of their citizenship.
What exactly did Trump say, how likely is any of this to happen, and what's the broader context around these statements?
Here's a look at some key questions and answers.
Asked by a reporter earlier this month whether he'd deport Musk, Trump said, 'I don't know, I mean, we'll have to take a look.'
He made a similar statement when asked by another reporter what he'd do if Mamdani defies US Immigration and Customs Enforcement in New York City.
'We'll have to arrest him. Look, we don't need a communist in this country, but if we have one, I'm going to be watching over him very carefully on behalf of the nation,' Trump said.
The president went on to add: 'A lot of people are saying that he's here illegally. We're going to look at everything.' There is no evidence that Mamdani is in the country illegally, though a conservative lawmaker has called for an investigation into his citizenship.
Musk and Mamdani are both naturalized US citizens. Musk was born in Pretoria, South Africa, and became a US citizen in 2002, according to biographies of the billionaire. Mamdani was born in Kampala, Uganda, and became a US citizen in 2018.
Regarding O'Donnell, Trump posted on Truth Social that the comedian 'is not in the best interests of our Great Country.'
'I am giving serious consideration to taking away her Citizenship,' Trump wrote, calling the US-born actress a 'Threat to Humanity.'
It was the latest volley in a longrunning feud between Trump and O'Donnell that's frequently played out on social media. Trump hasn't said what prompted his latest post.
O'Donnell, who moved to Ireland with her 12-year-old child in January, had recently criticized how his administration handled devastating floods in Texas. O'Donnell said earlier this year that she was in the process of getting Irish citizenship as she has Irish grandparents.
Musk: In response to a video of Trump's remarks shared on X, Musk said: 'So tempting to escalate this. So, so tempting. But I will refrain for now.' Musk hasn't responded to an inquiry from CNN about Trump's comments. In the past, the billionaire has denied accusations that he began his career working illegally in the US.
Mamdani: The New York mayoral hopeful decried the president's comments in a press briefing the next day: 'Yesterday, Donald Trump said that I should be arrested, he said that I should be deported, he said that I should be denaturalized, and he said those things about me, someone who stands to be the first immigrant mayor of this city in generations, someone who would also be the first Muslim and the first South Asian mayor in the city's history. And he said these things less so because of who I am, because of where I come from, because of how I look or how I speak. And more so because he wants to distract from what I fight for.'
O'Donnell: The onetime cohost of 'The View' fired back on Instagram, comparing Trump to a notoriously petulant and evil 'Game of Thrones' character: 'you want to revoke my citizenship? go ahead and try, king joffrey with a tangerine spray tan. i'm not yours to silence. i never was.'
Musk, Mamdani and O'Donnell are all high-profile figures whose political differences with the president are well known. But Trump's comments regarding their citizenship aren't happening in a vacuum.
In the recent past, denaturalizations were rare, averaging only 11 cases per year between 1990 and 2017, according to the Immigrant Legal Resource Center. The number of filings increased after the Justice Department opened an office focused on denaturalization during Trump's first term.
That office was quietly closed during the Biden administration, but the second Trump administration has made no secret of its desire to increase denaturalization as part of its immigration crackdowns. Stephen Miller has vowed the renewed effort will be 'turbocharged.'
And a memo issued by the Justice Department last month directed attorneys in the civil division to prioritize denaturalization 'in all cases permitted by law.' The memo also suggests that US attorneys' offices across the country should flag cases where they may be able to initiate denaturalization proceedings.
It's unclear whether the Trump administration will act on the President's comments referencing the citizenship of Musk, Mamdani or O'Donnell.
'Trump's words don't always tell us what he's going to do. It's sort of hard to know what to make of it,' says Matthew Hoppock, an immigration attorney in Kansas who's represented clients in denaturalization proceedings.
'I don't know if we should take him at his word, because a lot of these (comments) are not planned statements; they're in response to things that journalists say,' he adds.
And in the past, when the Trump administration announced plans to increase denaturalization during his first administration, the number of cases officials ultimately pursued was smaller than promised.
During the first Trump administration, US Citizenship and Immigration Services announced it would refer 1,600 denaturalization cases to the Department of Justice.
In the end, just over 100 denaturalization cases were filed during Trump's first term, according to the Justice Department.
The US law used to revoke the citizenship of naturalized Americans outlines two general grounds for such cases:
-Illegal procurement of naturalization
-Concealment of a material fact or willful misrepresentation
For years the statute was used largely to target war criminals, including former Nazis who lied their way into becoming American citizens.
But denaturalization is rare. And for the government, accusing someone of concealing a material fact in their application or becoming a citizen illegally is just the beginning.
'It still has to be a process which happens before a federal district court, and … the government has the burden of proving it by clear and convincing evidence,' says Muzaffar Chishti, a senior fellow at the nonpartisan Migration Policy Institute.
And winning that case in court can be difficult.
'Trump cannot denaturalize either Musk or Mamdani. Only a court can. And there's a process. And a high bar for that,' Chishti says.
O'Donnell is a US citizen who was born on New York's Long Island.
Experts say a president can't unilaterally take away the citizenship of someone who, like O'Donnell, was born in the US. The law outlines a series of circumstances under which someone can lose their citizenship if they perform certain actions voluntarily 'with the intention of relinquishing United States nationality.'
'Under the law, there is no mechanism for any natural-born United States citizen to lose their citizenship other than by renunciation (giving it up voluntarily) or death,' Hoppock says. 'Even if Congress created some law making it possible, the Supreme Court has held that such a law would be unconstitutional.'
Earlier this month, Justice Department spokesman Chad Gilmartin said five denaturalization cases had been filed since Trump's return to power. 'MORE TO COME,' he wrote on X in a series of posts that included a page from the memo outlining the Justice Department's updated guidelines for the practice. Gilmartin's post did not provide additional details about the filed denaturalization cases.
A June press release from the department describes the recent denaturalization of a former US Army soldier who pleaded guilty in 2014 to receiving child pornography.
The Justice Department's recent memo notes that attorneys should aim their denaturalization work to target anyone who poses 'a potential danger to national security.' It also says people who've committed violent crimes, are members or associates of gangs and drug cartels or have committed fraud should be prioritized.
Some immigration law experts have expressed concern that the memo could lead to the administration retroactively searching for missteps in the naturalization process of perceived political opponents.
'The politicization of citizenship rights is something that really worries me,' Cassandra Burke Robertson, a law professor at Case Western Reserve University, told CNN.
The Justice Department told CNN in a statement earlier this month that denaturalization proceedings 'will only be pursued as permitted by law and supported by evidence against individuals who illegally procured or misrepresented facts in the naturalization process.'
Chishti, of the Migration Policy Institute, says Trump's comments about Musk and Mamdani signify a notable shift in the way denaturalization is being discussed.
'This is a totally different chapter of going after your political enemies that has no precedent really,' he says. 'It's not that we have had no record of denaturalization. But political animus has never raised its ugly head in our process. This seems clearly driven by political motivation. And that's unfortunate.'
Hoppock says the president's recent comments about O'Donnell appear to be in a similar vein.
'It's an extremely concerning signal from a President that seems to have no concern for the Constitution,' he wrote in an email.
When asked for a response, White House spokeswoman Abigail Jackson did not address the specific claims made by Chishti and Hoppock, but questioned their expertise and noted they'd donated in the past to Democrats.
Taken alone, Chishti said Trump's comments about Musk and Mamdani might not have much of an impact. But coupled with the government deciding to revoke visas and green cards for people based on political opinions and foreign policy, he says, the potential chilling effect is clear.
'People, even naturalized citizens, will start being careful about anything they say. Because…even the success of the case is not important. It's the fact that…exercising your First Amendment right of expressing your opinion could land you in a denaturalization proceeding. That's very troubling,' Chishti says.
CNN's Hannah Rabinowitz, Donald Judd, Kit Maher and Hadas Gold contributed to this report.