Security is mostly a superstition. It does not exist in nature, nor do the children of men as a whole experience it. Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure, or nothing.
When I am seriously composing, sometimes a phrase will come into my head, a catch phrase. When I was writing pop songs for a few years, as a career, separate from my folksinging career, I used to write songs for pop singers.
Because you want to have competition to drive down the price. You want innovation. You have the ability to get people to agree that it's worth having a public plan. You could get private insurers to cover this population, but you couldn't without giving the population leverage in the marketplace.

