Financial markets rallied after the G20 news, though this was as much because of sprigs of good economic news emerging as the harmony that was displayed.

This was despite disappointment that the European Central Bank had cut its main interest rate on Thursday, by just a quarter of a percentage point, to 1.25%. American unemployment figures today , which can be shocking, may puncture some of that optimism, and should temper any temptation among G20 leaders to claim success. Their efforts to reflate the world economy may have avoided a 1930s-style depression so far. But rising joblessness and years of pain may lie ahead as banks, businesses and households in the West continue to struggle to pay down their debts.