This matters because the conflation of the two categories tends to helps those arguing against (a) migration and (b) legal guarantees for foreigners.

It’s not the same as the ‘removal’ of those with no legal right to be here, such as overstayers and unsuccessful asylum applicants. That does not usually involve serious criminal offences, and no conviction is needed.

Despite its manifest and massive unfairnesses, this would all be legally achievable if a majority was held. The UK constitution is just not equipped to prevent such extreme policies being implemented.

For those without permission, the Rules could though be changed to make ILR impossible to acquire.

At the domestic level, for those with existing immigration permission, it would mean amending the Immigration Act 1971, section 3: it prevents conditions being attached to ILR.

There is also a Windrush issue: ILR was conferred automatically by section 1(2) of that Act upon pre-1973 residents.

If EEA nationals were included, the Withdrawal Agreement and parallel agreements would also have to go.

At the international level, it would conflict at least with Article 8 ECHR (right to private life), and Article 3 of the European Convention on Establishment (secure residence after 10 years)...