If the court does overturn the mandate, it's going to be hard to know how to react. It's been more than 75 years since the Supreme Court overturned a piece of legislation as big as ACA, and I can't think of any example of the court overturning landmark legislation this big based on a principle as flimsy and manufactured as activity vs. inactivity. When the court overturned the NRA in 1935, it was a shock — but it was also a unanimous decision and, despite FDR's pique, not really a surprising ruling given existing precedent. Overturning ACA would be a whole different kind of game changer. It would mean that the Supreme Court had officially entered an era where they were frankly willing to overturn liberal legislation just because they don't like it. Pile that on top of Bush v. Gore and Citizens United and you have a Supreme Court that's pretty explicitly chosen up sides in American electoral politics.Why do I say it's only a potentially good point?
Because there's another possibility here: that the SCOTUS conservatives don't care at all about ACA or partisan positioning, but instead really do want to return Constitutional doctrine to where it was before the New Deal.
In my view, it was the wrong interpretation of the Constitution then and would be wrong now...but it's not really just plain naked partisanship on the part of the Court's conservatives if that's what they believe. And there's of course reason to believe that a lot of people do believe it that theory of the Constitution.
However, if we get a 5-4 decision that doesn't challenge the New Deal but relies on fatuous broccoli stories to knock out part or all of ACA...yeah, that's pretty much as close as you can get to substituting the Supremes' partisan-derived policy preferences for the decisions of Congress and the president.