Last week, India’s Prime Minister Narendra Modi banned from circulation the country’s two largest denomination banknotes, of 500 rupees ($7.50) and 1000 rupees ($15). The shocking move—kept secret and set to take place overnight—was intended to flush out the cash hoardings of black market participants and stop the corruption currently permeating all levels of business and government in India. The two banknotes, rumoured to account for almost 80% of the cash in circulation, were used primarily to avoid paying taxes and to pay bribes. However, the rupee ban has managed only to create chaos and...