Instead of quietly winding down the meritless investigation of US Federal Reserve Chair Jerome Powell, the Trump administration has ramped it up, with prosecutors showing up unannounced at the Fed’s construction site. But the president's political charade will only delay the confirmation of Kevin Warsh as Powell’s successor.

WASHINGTON, DC—US President Donald Trump has three goals for the Federal Reserve: He wants a new chair; he wants the current chair, Jerome Powell, off the Fed’s powerful interest-rate-setting committee when his term ends on May 15; and he wants lower long-term interest rates. But Trump’s own vindictiveness and lack of discipline are thwarting all three goals.