The region’s two largest jurisdictions — demographic cousins with populations around 1 million, school systems among the nation’s biggest and best, and public spending equal to that of small countries — have parted ways. To put it bluntly, Montgomery is lurching under the weight of irresponsible governance, unsustainable commitments and political spinelessness — particularly in the face of politically powerful public employees unions.

Over the past few months, some readers have asked why we lately have devoted attention to those unions. The diverging paths of Montgomery and Fairfax provide one explanation. We respect the public employees in both counties and their dedication to public service. Clean parks, cheerful classrooms, safe streets, bustling libraries — the work of these employees helps keep these counties such attractive places to live. But when 80 percent of all outlays are related to personnel, labor contracts that get out of whack can endanger the public welfare. . . . The cozy ties between elected officials and public employees unions in Montgomery have formed the backdrop for a drumbeat of reports about county employees’ bountiful benefits, perks and abuses. . . . Montgomery’s teachers union has wielded such outsized electoral clout that politicians who received the teachers’ endorsement in the most recent elections reached into their pockets and wrote checks to the union.

Public employees — who function without the discipline of markets, and apparently, politics — should not be allowed to unionize.