Following the terrorist attacks of 9/11 and the revelation of Iran’s secret nuclear programme, North American and European government officials and those working in law enforcement began emphasizing the importance of financial datamining in combating terrorism and nuclear proliferation. There was a growing belief that financial data could be used as a way to prevent terrorist attacks and that increased financial transparency requirements would discourage global banks from keeping and managing the money of customers designated by the United Nations Security Council (UNSC) for their role in the illicit nuclear programmes of Iran or North Korea. Law enforcement and regulators came to view financial information as far more reliable than other forms of intelligence when it came to conducting post-hoc analysis of sanctions violations and convincing global banks that the risks of detection were too high for them not to care about the international community’s efforts to combat either terrorism or nuclear proliferation. As then US Treasury Secretary John Snow argued, ‘money trails don’t lie’. Those banks that accompanied the change constantly updated their practice by co-opting the datamining technologies that they had been using for commercial purposes in order to profile their customers and determine client profitability in order to help pinpoint, amongst millions of financial transactions, the few suspicious withdrawals and transfers that could potentially indicate terrorist or WMD financing: these banks were the ‘good citizens’ of the banking com-munity, in contrast to the ‘bad banks’ that resisted the idea of increased transparency through mass surveillance of digital transactions and the automatic exclusion of suspicious clients and the freezing of their assets.