Thursday’s news crescendo ending in a calamitous presidential press conference carried hidden lessons for both parties: Be careful what you wish on your political enemies. It could monumentally backfire. The Democrats’ continuous calls during his four years in office to use the 25th Amendment to remove President Trump from office on the presumed grounds of mental instability took a disastrous turn this week, as the effort self-combusted in a Hindenburg-sized blowback. In October 2020, before Joe Biden was elected president and three months before Trump supporters stormed the U.S. Capitol, then-House Speaker Nancy Pelosi held a press conference. She was...