Which Western nation has implemented (and I mean properly implemented) a policy like Rwanda previously?
You don't think the likelihood (and it would have to be a likelihood) of getting shipped to Rwanda would be a deterrent to economic migrants trying to come to the UK?
The question wasn't do I know any, the question was about whether or not analysis had gone into the policy making.
So no idea why you are asking.
Re: whether it's a deterrent or not.
Possibly. Before being able to give even a moderately robust view I'd need to know a lot more about the backgrounds of recent illegal migrants - what was the driver for migration, what were the facilition factors (people trafficed; gang related with payment after obtaining work here; payment up front; collateral (IE endangered family if certain conditions not met); access to information in their country of origin (IE do they know about the Rwanda policy in detail and still made the choice to come? Do they have adequate to the information etc etc)).
These are just for baseline off the top of my head and from my limited understanding. They are also before further requirements are identified during policy development discussions.
For what it's worth - I'd take a different approach. The data above should help to identify routes and origins of the people that put their lives at risk to come here.
The immediate question is - why? Looking at it from a national governance point of view, if I don't want illegal migrants (note - distinct from asylum seekers), I need to understand why it's better for them to be here than there (wherever there is) and I either look to work and/or punish the nation of origin.
Despite (in spite of?!) Brexit, the UK is still a huge global player and will very likely have influence over the countries of origin.
Instead of targeting the victims, target the people creating/perpetuating the issues.