Inevitably, once it becomes known that interacting with the British state puts illegal migrants at risk of deportation, many of those people will slip into the parallel economy which already exists for illegal migrants — of cash-in-hand businesses, and unscrupulous landlords.

Finding and apprehending those people will, at some point, mean conducting physical raids. Who will carry out those raids? Will it be Border Force, the police, or some new institution? How will we find the staff for those institutions, and quickly? How can finding those staff be reconciled with a desire to scale up the workforce in other parts of the state which will tend to attract similar people — like the police, or the prison service? How can we ensure that those people have adequate training, to avoid the kind of heavy-handed thuggery which has turned American public opinion against ICE?

Will all members of the Government, in Parliament and beyond, be prepared for the inevitable fallout? Are they emotionally and personally prepared for it? Are other areas of policy — plans for the economy, for training and education, for welfare — geared towards making sure that the right sections of the public feel the positive impact of these changes over the course of a five-year Parliament?

What action can be taken against businesses that hire people illegally, to make this option more difficult for illegal migrants? What action can be taken against landlords who rent to illegal migrants? How do we plan to deal with the inevitable resistance, from both the political left and from heavily-migrant communities?

Once those people have been apprehended, where will we put them? If new facilities are required, how quickly can those be built? If those detention facilities are in areas with organic local resistance to the removals agenda, are we prepared for the policing and security implications of this? If those detention facilities are in areas which support the removals agenda, how can we politically reconcile putting thousands of illegal migrants in communities which voted to get rid of those migrants, even if they are only held there temporarily?

Of course, this policy agenda will not be taking place in a vacuum. Other countries will notice, including countries to which we may need to remove many thousands of people. Those countries may refuse to take people, even if we are in a position to remove them. When confronted with this fact, people tend to fall back on threats — of suspending aid, or suspending visas, or taxing remittances.

But how many diplomatic fights will we need to have? How many are we prepared to have — and for how long? What problems can those countries cause for us — particularly, as in the case of India, Pakistan, and Bangladesh, where foreign countries are able to tap into large diaspora networks of British citizens in this country.

Is there a way to reduce resistance from foreign countries, in some cases, by taking a less confrontational approach? Are we willing to negotiate? If so, what concessions are we willing to make, in each case? How can those concessions be sold to a domestic audience, many of whom will have voted in favour of a more assertive and self-interested approach to foreign policy?

As policy-makers move to answer those operational questions, they should bear in mind three dangers.

The first danger is that legitimate operational concerns are dismissed out-of-hand as left-wing hand-wringing, or defeatism. It’s true that elements within the Home Office, and within other parts of the civil service, have worked to undermine attempts by previous Governments to increase removals and control migration. Most often, they have done so by presenting certain legal or practical tradeoffs as intractable problems which necessitate the maintenance of the status quo.

There is a difference between raising practical questions about this policy agenda, and attempting to undermine the agenda. For plans to be effective, they must be rigorously tested, questioned, and probed. It is not enough to rely on “common sense”.

The second danger is that the work simply doesn’t happen. This is a very real risk. The British right has very few policy thinkers capable of drawing up a proper operational plan for mass removals. The time and attention of those people will be dragged in many different directions over the next few years. There will be a tendency to imagine that somebody must be doing the work, even if this isn’t really true.

If nobody does the work, in the requisite detail, then a new government will quickly find itself overwhelmed by events. It may not get to implement its policies on deportations until it has spent its first year unpicking our human rights law architecture; it may not begin to see a meaningful increase in the number of removals until the very end of the Parliament. It will be up against civil servants, charities, and activist lawyers, all of whom have spent years thinking about this issue, in detail, and who have a material interest in maintaining the status quo. If we do not plan, they will beat us, every time.

The third, and most pressing, danger is that operational plans may be driven by emotional catharsis, rather than by a clear-eyed desire to fix the problem. As Alex Yates rightly noted in his own piece on this subject, “ICE’s increasing unpopularity amongst the American electorate, a plurality of which voted for a candidate on a ticket of ‘mass deportations’, shows that what may gain popularity as a slogan or as a neutrally-toned polling question can rapidly lose support once the reality of its implementation becomes clear and the human suffering is necessarily causes becomes real.”

He is equally right to note that, in tone and in substance, “removing someone with no right to be in Britain should be treated as an unfortunate but necessary role of any responsible government…and not a way to get a kick out of tormenting foreigners”.

The difference between success and failure is in the quality of our plans

For people who have, rightly, recognised the enormous harm wrought by mass migration, it will not necessarily be satisfying to fix the problem in a way that’s understated, and which appears outwardly inoffensive. Indeed, many of those people will try to convince themselves, and others, that only the most bellicose tone and approach will get this agenda over the line. This has not worked in the United States. Revelling in deportations has hardened and emboldened the staunchest critics of that agenda, and turned many moderates away from the project.

None of these practical considerations should be taken as arguments for the idea that mass removals cannot work. In fact, the opposite is true — Britain cannot work without mass removals. If we believe this to be true, we should recognise the importance of getting things right. The difference between success and failure is in the quality of our plans, and in the quality of the people charged with implementing those plans.