Financial systems are not state or market, private or public, but always and necessarily both. This follows from the facts that financial instruments must be enforceable, that finance is hierarchical and that in the last instance a sovereign has to stand in to protect the financial system from self-destruction. Describing finance as a system of private/private commitments subject to some (external) constraints that may enhance market efficiency misses much of what is unique to contemporary finance: It is based on money as the legal tender, relies on the legal enforceability of private/private commitments and in the last instance depends on backstopping by a sovereign. Indeed, the scale of today’s transnational financial markets would not be feasible without their legal backing, even as the very size of financial markets  thus created pushes the limits of what sovereigns are willing or able to provide, individually or collectively. The essential hybridity of finance thus also points to where ultimate power over finance rests: with the polities that are backstopping the system. Central bankers may have replaced their voices by speedy action for now: ‘‘Forget the G7 – Watch the C5.’’ And yet, their effectiveness ultimately hinges on the legitimacy of their actions in the eyes of the public that entrusts them with their discretionary powers.