You can read all of Chief Justice John Roberts' opinion upholding health insurance subsidies for the 34 states with federal Obamacare exchanges. But you can also understand it by reading this one sentence:
Roberts: "Congress passed the Affordable Care Act to improve health insurance markets, not to destroy them." pic.twitter.com/4y3injI9re
— Jordan Weissmann (@JHWeissmann) June 25, 2015
It's a simple argument: the point of Obamacare is to make health insurance markets work better and cover more people. To change the law so as to make them work worse, Roberts concluded, is to betray its clear intent.
Read more about the case in our card stack here: