Donald Trump’s Twitter outbursts over the sentencing of Roger Stone were inappropriate and self-defeating. But the most disturbing part of the Stone saga was reporting last week that the Federal Judges Association leadership had scheduled “an emergency meeting” to rebuke the President. That suggested the judiciary was mobilizing politically—a prospect that delighted the resistance to Mr. Trump but is a danger to the rule of law.

The meeting was postponed amid the press deluge, and the good news is that the FJA is now saying…