Almost Every western country is in a massive hole of debt, the us included.
I think it is more sustainable than other systems, especially the one practiced in the US.
Also, please note than in the US, public spending on health is already huge, and there’s a huge private spending as well - iirc about 20% of us GDP is spent on healthcare, which is double any other western country, and with worse results to boot. It is already unsustainable.
