What is the constitutional authority by whichthe federal establishment would contribute condition insurance . . . ?

to its citizens.

I know it insures employees, but that's when the government act as an employer.

Where is the constitutional authority for providing health coverage?

And yes, the question could apply to Medicare also.

Is this a state function, if a elected representatives function at all?
Answers:
In the preamble the Constitution it does read aloud that a function of the United States is to "...promote the general welfare..." of the people. Although I know of no court ruling stating that the preamble is an enforceable portion of the Constitution, I also know of no rulings saying that it is not.
I know that some relations will cite the "general well-being"
bit and say that GOVERNMENT have the duty to provide Health-care
HOWEVER,

It WILL be poorly run, rationed, filled next to bureaucrats ....

In short, they gonna ruin it! Get the Government OUT of as many areas as possible, they run the ARMY, NAVY (etc....)
and collect the min. tax to support said Army, but let not get carried away!

Governments Govern by the CONSENT of those Governed
(otherwise all you enjoy is a Dictatorship)

Does the administration have YOUR consent?
They probably mask it below the right of the federal government to regulate trade between the states. But you are right, this is not a Constitutional authority that I can see.
Preamble to the Declaration of Independence states, ..."life, nouns, and the pursuit of happiness." You cannot have natural life, liberty and the pursuit of happiness minus having affordable health fastidiousness. Most likely amendments would be Article 9 and 14
it doesnt!

Your own life, sovereignty and happiness is what YOU can make of it!


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