Photo by WANG ZHAO/AFP via Getty Images Since Vladimir Putin started his war against Ukraine in February 2022, the Russian rouble has behaved like a yoyo, jumping up and down. In summer 2022 the Central Bank of Russia managed to restore the value of the rouble, but it is not likely to happen again. Recently its value plummeted from 73 roubles per US dollar to 100 roubles per dollar and it has since stayed in the nineties. Western financial and energy sanctions are biting, as well as Russia’s increased military costs. This is a significant blow to Putin’s domestic credibility....