"Somebody who has spent a lot of time in the caliphate is likely to be radicalized, and women are as capable of committing terrorist acts as men," said NBC News security analyst Duncan Gardham. "It may be a difficult task to make sure she is not radicalized and ensure that she's not a threat."

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

The stereotypical image of foreign fighter tends to be male, like Albert Berisha, a Kosovar man interviewed by NBC News last year who traveled to Syria to fight the government of Bashar al Assad and claims he accidentally fell in with an ISIS unit.

Prosecuting returnees who have committed crimes with ISIS, however, raises issues about where to incarcerate them — without risking radicalizing other inmates — and what to do with them upon their release, Shiraz Maher, director of the International Centre for the Study of Radicalisation and Political Violence, at Kings College London, said in a tweet thread on Thursday.

Again, it's not clear how deep Begum's involvement with ISIS went, but she should be treated no differently, in terms of the potential threat she poses the U.K., because she is pregnant, Gardham said.

Last year, two sisters and their mother were jailed as part of an all-female terror cell that wanted to carry out an attack on British soil. In 2016, a British woman, Tareena Shakil, 26, was jailed for six years for taking her young son to Syria and joining ISIS.

If there is evidence, Begum could be arrested for joining a banned terror group, or for merely deliberately staying in what the British government calls a "designated area" — essentially a war zone like Syria.

Even if she is classified as a noncombatant, the importance of her merely being in Syria should not be dismissed, Maher said.

Their presence in ISIS territory alone represented "a type of moral and propaganda victory for the group," he tweeted. "Don't underestimate how important that was."

But whatever you think, there is very little public sympathy for those who voluntarily migrated to Islamic State. That strengthens the hand of our governments who are adopting a position of passivity towards this problem. They’re happy to embrace the omission. 27/ — Shiraz Maher (@ShirazMaher) February 14, 2019

Her legal status might be the easy bit. Morally, there has already been a wide public disagreement in Britain about whether Begum can and should be rehabilitated back into society.

In 2015, she was widely portrayed as the 15-year-old victim of online brainwashing, someone who needed to be saved from the clutches of a murderous death-cult.

Now, her unapologetic interview in The Times has led many to say that she should be left to her own fate.

Security minister Ben Wallace pointed out that as a British citizen Begum had the right to return to the U.K. However he said she would at least be investigated by counterterror police and suggested that the public’s safety would take priority.

"I'm not putting at risk British people's lives to go and look for terrorists or former terrorists in a failed state," he said on BBC radio early Thursday.

British teenagers Amira Abase, Kadiza Sultana and Shamima Begum walking with luggage at Gatwick Airport, south of London, on Feb. 17, 2015. Metropolitan Police Service / AFP - Getty Images file

Officially, it is U.K. policy to tell British women in this situation to get themselves to the nearest consulate to be repatriated. Unofficially, the government "would rather they did not come back," Gardham said. "They don't want jihadi brides back and they don't want jihadis back."

This stands in contrast to the approach of the U.S., which has been more likely to take on and prosecute alleged terrorists, Gardham added.

This difference in strategy has been seen in the case of El Shafee Elsheikh and Alexanda Kotey, two surviving members of an ISIS execution squad known as "The Beatles," who have been stripped of their British citizenship and could be extradited to the U.S. for prosecution.

Sir Mark Rowley, former head of British counterterrorism policing, agrees the U.K. will likely display a passive attitude toward Begum.

"I don't imagine the Foreign Office will be rushing into Syria to try and get hold of her," he told BBC radio Thursday morning.

If Begum were to return and be arrested, the problems would not stop there.

"I think actually the biggest challenge would be if she did come back," Sir Peter Fahy, the former head of Britain's counterterrorism program Prevent, told BBC radio.

"How the local police would keep her safe and how it would be ensured she would not be some sort of lightning rod," he added, "both for right-wing extremists and Islamic extremists, and that she wouldn't somehow try to justify her position and what she did."