After Hillary Clinton’s devastating loss nearly six months ago, her most powerful Democratic allies feared losing control of the party. Efforts to lip-synch economic populism while remaining closely tied to Wall Street had led to a catastrophic defeat. In the aftermath, the party’s progressive base—personified by Bernie Sanders—was in position to start flipping over the corporate game board.

Aligned with Clinton, the elites of the Democratic Party needed to change the subject. Clear assessments of…