Early Friday morning, Senate Republicans failed to pass a "skinny" version of the Obamacare repeal bill, which would have left 15 million more Americans without health insurance by 2018. This is a devastating blow to Senate majority leader Mitch McConnell, who has been working hard to pass any repeal bill at all for weeks. His failure means that a major item of the GOP agenda has stalled, maybe permanently; it's also a blow to his personal reputation as a dark master of the Senate.