As the Kremlin took urgent measures to stabilise the plummeting rouble last week, one thing became clear: rampant spending on its war machine and social welfare programmes could not go on for ever. Few observers believe the Russian economy is in danger of imminent collapse. But it has reached a point, they say, where the Kremlin may have to weigh the cost of spending trillions of roubles on its war with Ukraine, and withstanding unprecedented sanctions, while maintaining prewar levels of public spending. “In the grand scheme of things, as long as Russia continues to spend so madly – both…