I'll differ a bit that anyone who is here legally is covered rather than citizenship. We waited 6 years for our citizenship and did emmigrate legally in 1961.
So much change required at the legislative level. Any facility that receives ANY federal funding (ie: Medicare, Tricare, Medicaid), is required to care for all who arrive. Hence the ER care given to uninsured and illegal aliens. Funding is at risk if anyone is turned away.
And that's just the beginning of the cascade of Legislative change needed. sigh....................