Is the party not-in-power really the responsible actor?

I don't understand the question.

I'd say that as human beings, we're obligated to help those who have less, so in that sense, we /are/ individually mandated to action, but that action can be carried out simply by paying taxes. I admire HCPs who volunteer at indigent clinics, but making free clinics unnecessary would be better. But the second half of your sentence works.