Just over four months ago, the U.S. and several allied nations levied unprecedented sanctions against Russia in response to its invasion of Ukraine. For weeks afterwards, the Russian ruble's value tanked, foreign multinational companies pulled out of the country, and economic prospects began looking grim. But Russia responded aggressively. It shored up the ruble's value and increased oil exports to China and India. The ruble is now the world's strongest performing currency. Thanks to years of preparations, Russia has become far more self-sufficient, and has massive foreign exchange reserves. It has also reopened several companies that were previously under foreign...