Every mass shooting in the United States is greeted with a depressingly familiar response: heartfelt cries of anguish, calls for Congress to take action, GOP stonewalling, and then the status quo ante until the next tragedy. It doesn’t matter that tougher gun laws like universal background checks have overwhelming public support, even among NRA members. The power of the gun lobby remains too strong, and votes for gun control mean no campaign contributions, poor NRA ratings, and perhaps a primary challenge in the next election. So nothing changes, and sooner or later attention fades.