The Republican establishment has plowed millions of dollars this year into primaries to produce what it views as a less dysfunctional House GOP conference. It’s still got a long way to go. Major Republican leaders and donors have notched some key victories in their ongoing war against far-right insurgents who threaten the ability to govern as a unified party. But even those successes have come at a cost: the enormous amount of effort, money and time it’s taken to push their...