BUILDING A BIGGER ASH HEAP:

The US, Europe, Australia and Japan responded with sanctions which were deliberately designed to target a small number of wealthy Russians. But Putin broke new ground again. Instead of responding in kind, he banned food imports from the West. Because Russia normally imports at least a quarter and possibly as much as half of its food -- not only Parmesan from Italy but frozen vegetables from Poland -- he ensured that food prices would rise, not just for a small number of people but for the entire nation. It was a calculated risk: the Russian President and his entourage apparently reckoned that the Russian people would agree to pay higher prices for food in exchange for military glory. Unlike decadent Europeans and spoiled Americans, Putin seemed to believe that Russians would stoically suffer on behalf of the motherland at a time of crisis.

Was he right? We are about to find out. This week the rouble, which has lost a third of its value in three months, slid by 9 per cent in a single day. A recession is now predicted. Inflation is predicted too, as high as 8 or 9 per cent. A controversial but long-planned pipeline construction has been abruptly cancelled. Major Russian banks are asking for government loans. Russian companies which earn in roubles and borrow in dollars are suddenly in trouble. Capital has been swiftly flowing out of the country, and some banks are rumoured to be limiting withdrawals. There are so many rumours about capital controls that the prime minister, Dmitri Medvedev, has explicitly denied them.

Not all of Russia's economic disruption is caused by sanctions, of course. Since last spring, oil prices have also dropped by nearly 40 per cent. The world's largest oil producer, Saudi Arabia, has just made it clear that it won't lower production in order to push them up again, at least for the time being.

This might not matter as much to other oil producers, but for more than a decade Putin has coasted on the illusion that historically high oil and gas revenues could both support the national budget and disguise Russia's failure to create a more productive economy. High energy prices even paid for the excesses of autocracy and an expansionist foreign policy: the Sochi Olympics, the billionaires' palaces, the adventure in eastern Ukraine, the military exercises on a Cold War scale, even the €9 million loan which a shady Russian bank has just made to the far-right French National Front.

Sanctions have exacerbated the difficulties created by the collapse in oil prices, and in this narrow economic sense, Putin's experiment has failed, or at least proved to be very expensive.

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