India is not the first country to introduce abrupt, drastic reform of its currency. But the precedents—including Burma in 1987, the former Soviet Union in 1991 and North Korea in 2009—are not encouraging. Burma erupted in revolt, the Soviet Union disintegrated and North Koreans went hungry. All the more reason for Narendra Modi, India’s prime minister, to prepare the ground before the surprise announcement on November 8th that he would withdraw the two highest-denomination banknotes (the 500-rupee and 1,000-rupee, worth about $7.30 and $14.60). Yet he did not and the result is a bungle that, even if it does achieve its stated aims, will cause unnecessary harm.