You’re doing a great job convincing the other side! Words like “uncivilized” and a crack about how bad America is is definitely growing support for your position!
I understand your point, humans are emotional creatures.
But catering to feelings over facts seems directly responsible for a lot of the messes and "leadership" we have across the first world right now. I hope we can grow past it.
Their class interests are directly opposed to those who most need universal healthcare.
That's not even wrong. The only people whose interests are against those who would benefit from universal health care are those who work in the insurance industry. Literally everyone else would benefit from universal health care because it contains the damage wrought by the externalities of illness and injury.
Employers benefit from universal health care because they no longer need to manage health benefits for their employees. This also removes a barrier to hiring, allowing employers to hire more employees with less risk.