Last week, Warwick Lightfoot — Policy Exchange’s Director of Research, and Head of Economics and Social Policy — appeared on the BBC World Service to discuss Steven Mnuchin’s appointment as US Treasury Secretary. Lightfoot discussed the new American administration’s tax-reform agenda, and the complexity of the US income-tax regime that, in its different marginal tax rates, looks like a ‘Manhattan skyline’. He also talked about how the US Treasury Department plays a central role in policing international financial transactions, as part of the US Government’s counter-terrorist policies. This is a role, he explained, that is entirely consistent with the department’s history: the US Secret Service is a department of the Treasury that was originally established in the nineteenth century to deal with counterfeit dollar bills.