Vermont apparently tried to setup a single-payer healthcare system, only to have various healthcare and pharmaceutical companies threaten to ruin them if they did so, at which point Vermont, a state not large enough to take them on, backed down.
Despite this, countries like Iceland have single-payer systems, and don't have to deal with things like nonsense pharmaceutical price gouging despite having only around half the population of Vermont, and six billion dollars less in GDP.
Why is it that Iceland can setup a single-payer system, but Vermont couldn't? What does Iceland have that Vermont doesn't? And how can these differences be generalized such to explain what the requirements are for a state, or country, or healthcare providing NGO to be able to run a single-payer system?