You assert that problems will crop up, but fail to mention which problems. You are arguing that any data anyone brings up is irrelevant, without bringing up any data.
You keep comparing the UK to the US, but a much more apt comparison is e.g. UK to CA, and the entire EU to the entire US. UK has twice the population of CA, and better bang/buck and health outcomes. EU compares similarly to the entire US.
The EU is at this point in time, a federation slightly more disjoint but ultimately of similar structure to the US.
Why not build an independent single payer healthcare system in each US state, with reciprocity among them? That is directly comparable to the european system, and has been shown to scale and work efficiently and well.
You keep comparing the UK to the US, but a much more apt comparison is e.g. UK to CA, and the entire EU to the entire US. UK has twice the population of CA, and better bang/buck and health outcomes. EU compares similarly to the entire US.
The EU is at this point in time, a federation slightly more disjoint but ultimately of similar structure to the US.
Why not build an independent single payer healthcare system in each US state, with reciprocity among them? That is directly comparable to the european system, and has been shown to scale and work efficiently and well.