As GOP operatives race to the spin room to tout their candidates’ performance in the Milwaukee debate, President Reagan’s 11th Commandment — “Thou shalt not speak ill of other Republicans” — is having its moment. All eight contenders embraced its enduring wisdom, setting their sights not on each other or the absent President Trump, but President Biden and the Democrats.

Like “My Way,” which Reagan’s friend Frank Sinatra joked he “stole,” the 40th president made the 11th Commandment his own, but he didn’t write it. The rule was born out of another contentious GOP primary, when California’s party chairman, Dr. Gaylord Parkinson, decreed that Reagan and his two rivals for the gubernatorial nomination should avoid inflicting fatal wounds on the eventual nominee.