[marcus_holmes]

Precisely my point about terrorist organisations; Palestine Action did not kill anyone, yet the UK considers them to be the same category of organisation as ISIS.

If I read this right, you're thinking that only naturalised citizens would be affected by such a law; those with dual nationality that can be "sent back to where they came from". Which explains why you think this is a good idea.

That's not how citizenship works. If you allow for removing citizenship, then all citizens, regardless of "primary" nationality, can be made non-citizens. There's no second-class citizenship that can be revoked while still retaining a first-class citizenship that cannot.