To the perhaps mutual chagrin of Vladimir Putin and Donald Trump, the Russian and US leaders’ chummy summit in Helsinki last month appears to have backfired. Instead of a thaw in ties with Washington, Russia is confronted by new US sanctions. Not only has Congress, apparently alarmed by Mr Trump’s deferential treatment of the Russian president, proposed stiff further measures to punish the Kremlin for its interference in American elections. Moscow is also facing bans on imports of US technology following the poisoning of a former Russian spy and his daughter in the UK in March with a banned nerve agent.

The sanctions amount to a tightening vice on Russia’s economy. The impact of US and EU measures imposed since Moscow’s 2014 annexation of Crimea may have been limited. Alexei Kudrin, a liberal ex-finance minister, estimates they have shrunk Russian gross domestic product by only half a percentage point a year. But they add pressure when growth is already stagnating.

Years of failure to diversify the economy away from reliance on energy and natural resource exports are coming home to roost. So, too, is lack of rule of law and protection for property rights. That is not only deterring foreign investment. It is encouraging predatory behaviour by officials towards local entrepreneurs. The new sanctions will further deprive Russia of western know-how and financing vital to modernise the economy.