Never-Trump Republicans crowned a new hero last week with the emergence of Rep. Liz Cheney, the party’s No. 3 leader in the House, who accused President Trump of the biggest “betrayal” in White House history and voted for his impeachment.

As the daughter of a former vice president, Ms. Cheney is as close to Republican royalty as exists in Congress right now, and her impeachment vote — and the fierce denunciation she delivered along with it — catapulted her over the likes Sen. Mitt Romney or former Ohio Gov. John Kasich.

Now, as Republicans ponder life without the reins of power, Ms. Cheney’s act of rebellion against the outgoing party leader has pointed the way forward for the wing of the GOP hoping to erase as much as it can of Mr. Trump and his policy positions.