The rebellion ended as quickly as it began. Less than a day after Wagner Group mercenary chief Yevgeny Prigozhin led thousands of his men into Russia and made a beeline toward Moscow, he called it off and pulled them back. In a deal brokered by Belarusian President Alexander Lukashenko, Prigozhin received immunity from prosecution — Russia’s Federal Security Service charged him with an act of insurrection, which carries a 20-year prison sentence — exile in Belarus and the ability to live another day. Russian President Vladimir Putin, who has been atop the Russian system for nearly 24 years, av...