The home secretary, Sajid Javid, has revoked Shamima Begum’s British citizenship. Begum left the UK with two friends four years ago, at the age of 15, to join Daesh. She now finds herself stateless, with a newborn and possibly British baby in a Syrian refugee camp. Public sympathy in the UK has been limited. Begum has said she wasn’t ‘fazed’ by the sight of severed heads in bins, and suggested that the Manchester Arena bombing was payback for airstrikes against Daesh territory. She has regrets, but little remorse. Still, she was born and grew up in the UK, and when she left as a child she had been groomed online by a criminal organisation.

The use of an administrative process to strip Begum of her nationality sets a worrying precedent, if you value the rule of law and are concerned that citizens be protected from tyranny. Someone who has been stripped of their nationality and made stateless loses most of the protections of the state. A dual national who is deprived of the nationality of the country where they have grown up, and where their friends and family live, faces removal to another country, nominally ‘theirs’, where they may know nobody and not speak the language. Legally they are members of that other place; functionally they are not.

Since 2010, successive home secretaries have increased the use of citizenship deprivation powers and widened the field of people against whom action can been taken. Citizenship may now be revoked for ‘serious criminality’. So far this has been used against the members of ‘grooming gangs’, transformed into ‘foreign criminals’ who can be sent ‘home’. Public reaction to their removal will often be ‘good riddance’, but once the precedent is established, others, guilty of less heinous crimes, can also be removed.

Defending deportation flights to Jamaica, Javid referred to those being removed as ‘serious criminals’. Many were guilty only of drug or even driving offences yet could be flushed from the system. They had never formally secured British nationality, but some had known no other home than Britain. The extension of citizenship deprivation potentially allows more people to be shifted to the category of the deportable.

The UK is a party to the 1961 Statelessness Convention and bound not to revoke someone’s nationality if they do not have another one to fall back on. In 2014, the Coalition government weakened the protection: naturalised citizens could lose their British nationality if the secretary of state had ‘reasonable grounds’ for believing they were able to acquire the citizenship of another country. Depriving naturalised citizens of their status is not unproblematic, since it divides society into those who hold their membership securely and those who do not. But at least when people naturalised as adults, swearing allegiance to their new state, it could be argued that they went against their word.

The naturalised are a tiny proportion of the citizens of most countries. Like most British citizens, Begum acquired her nationality at birth. In her case, Javid seems to be relying on her already being legally a citizen of Bangladesh, a country she has never visited. The government in Dhaka, however, has said that she is not a citizen and ‘there is no question of her being allowed to enter into Bangladesh.’

If Javid’s decision is not overturned by the courts, the vast majority of citizens, for whom losing their citizenship was literally unthinkable, may need to think again. So who is at risk? Potentially, any UK citizen who also holds the nationality of another state, whether they are aware of it or not. And certainly anyone who is naturalised and whose entitlement to another citizenship excites the ‘reasonable belief’ of the home secretary. Add these groups together and you have an awful lot of people.

Anyone in Northern Ireland who holds Irish nationality could be kicked out if this is believed conducive to the public good. Children whose parents thought it wise to get an Irish or other EU passport after Brexit now carry this hidden vulnerability. Every Jew has the right to Israeli citizenship. The British children of citizens of other EU states may grow up with a hidden nationality that makes it easier to kick them out later. And the same goes for those whose parents came from parts of the former British Empire, as in Begum’s case. You might think the government would never do that, even for ‘serious criminals’, at least if they were white and middle-class and with English ancestors going back a bit. You'd probably be right: those who are singled out to be redesignated as not British and marked for exclusion tend to have a ‘funny tinge’ about them.