This article assesses the extent to which bankers approached sovereign debt defaults during the interwar period according to norms established during the nineteenth century. Bankers treated postrevolutionary Mexico as a hybrid, that is, as a case of both developmental and revenue default, in Fishlow's taxonomy, in the interest of protecting the rights of bondholders generally. Their approach led them to reject the argument of US ambassador to Mexico (and former Morgan partner), Dwight W. Morrow, that a government could be financially insolvent. Bankers acted similarly during the debt crisis of the 1980s.