A possible unintended consequence of Trump's withdrawal, from the Paris Accord, is the fact that several of the wealthier States are going to join, on their own, and pursue action against climate change, in spite of action by the Federal Government.
It is not unreasonable to go from such a step, to forming a pool of several of those States, to draw on to set-up a single payer health care system for the citizens of those States.
If a Federation of States blocks activities, which will benefit the residents of those States, there is no constitutional reason that prevents a group of States, exercising their State's Rights, from forming ad hoc confederations, to protect their citizens
To prevent the citizens of what we now call the Red States from taking advantage of medical facilities in the more liberal States, a residency period, at least a year could be established.
Who knows what other services can be provided to our citizens by rational pooling of resources blocked by an irrational Federal Government.