//perhaps if we made more of an effort to keep them out in the first place.//
How do you suggest we do that? International Maritime Law places an obligation to rescue people in danger on the sea. This article explains it fully:
https://www.law.ox.ac.uk/research-subject-groups/centre-criminology/centreborder-criminologies/blog/2020/03/duty-rescue
It explains all the various conventions to which the UK is party. To save you reading it all, the bottom line says this:
“Non-assistance to refugees and migrants at sea is not a legal option.”
So unless and until the UK withdraws from these conventions they cannot be prevented from arriving here, whatever Ms Patel espouses. The secret lies in returning them whence they came.
//He'll never understand Brexit.//
He (Gulliver1) understands it perfectly. The secret is not to engage with anything he posts.