Vladimir putin, Russia’s belligerent president, has plunged his country not only into war but also into economic chaos. In response to his invasion of Ukraine, Western governments have imposed sanctions of unprecedented severity on Russia’s economy and financial system. An exodus of Western firms is under way. On March 8th Shell, Europe’s largest oil company, became the latest to say it would quit Russia. On the same day Joe Biden, America's president, announced a ban on purchases of Russian oil, the country's prime export.

Over the past two decades—but especially since his annexation of Crimea in 2014—Mr Putin has been trying to reduce Russia’s dependence on commodity exports and on Western technology and finance. But “Fortress Russia” is far from complete. In particular, Russia remains highly reliant on commodities, a dependency which not only hampers its long-term economic potential but also renders it vulnerable to shocks—of which sanctions are a stark example.

One gauge of this is Russia’s performance in the Economic Complexity Index (ECI), compiled by an economist and physicist at Harvard University. The ECI measures the variety of exports from a country and the technological know-how required to make them. The greater the variety of “complex” products, the higher the ranking. Although Russia boasts the world’s 11th-largest economy, and its ranking has improved, in 2019 it ranked only 52nd out of the 133 countries on the ECI because of its heavy reliance on natural resources (rather than complex manufacturing and technology, say). Seventeen of its top 20 exports by value are less complex than the average for all countries.

Russia’s ranking has risen in recent years: in 2012 it was 70th. Profits from oil made up 9% of GDP in 2019, down from 15% when Mr Putin took office in 2002. But its biggest export, crude oil, is ranked by the ECI as one of the least complex sectors in Russia’s economy. Compared to high-tech fields, such as integrated circuits and carmaking, natural resources offer less potential for spin-off technology and innovation that can fuel growth.

Sanctions are of course not costless for the West, either. An early threat by Antony Blinken, the American secretary of state, of an oil embargo to be imposed by America and its allies sent crude-oil prices near to $140 a barrel; some predict it could touch $200 if the war in Ukraine escalates. Europe is uneasily reliant on Russian natural gas. But Russia’s own dependence on energy exports makes it more vulnerable. Hence Mr Putin’s eagerness to diversify his economy. But he has not gone far enough—and he will find it harder when no one wants to do business with him. ■

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