Chief Justice John Roberts famously defined himself as an umpire in his confirmation hearings. But an umpire is willing to make the toughest calls.
In his Obamacare decision, Roberts the umpire blinked. By issuing a decision that forestalled the tsunami of criticism that would have come his way had he struck down the law (as an activist, a partisan, and an altogether rotten human being), Roberts effectively rewrote the constitutionally problematic portions of it. He overstepped his bounds. The umpire called a balk, but gave the pitcher a do-over. The ref called a foul, but didn’t interrupt the play.
As a result, there’s Obamacare as passed by Congress. Then there’s Obamacare as passed by the Supreme Court.