If a country is too far socialist or too far capitalist, the result is the same; the few gaining great power and privilege, while the many are powerless and suffering in poverty. Its obvious that a balance is needed, socialism can be very good at leveling the playing field for basic necessities, while regulated capitalism can be good at distributing power hierarchies while remaining fairly efficient.
The problem i see us facing right now is that capitalism has had a lobby on political power for fifty years and is preventing this balance, substituting its own power-wealth hungry pseudo-balance. This is why we have difficulty dealing with climate change, and why places like the US are struggling with a universal health system, or why the UK is dismantling theirs.
>Can you imagine any of this success without socialist schools?
Yes.
But to answer why people come here, I'd say they come for freedom and the hope of a future - and many try to stay. The east coast is full of Indian doctors who come here for their degree and have no intention of ever going back to India.
There are very few countries in the world that lived by the laissez faire rules of capitalism, because its been a disaster every time.