An auditing of who a country owes it's debt to seems a compelling argument. Especially when the austerity measures including cuts to health and social spending mean that the country's own people die so that offshore bankers get paid. Bankers and international financiers who lent money in the first place with interest that reflected the riskiness of the loan.
Often, as in the case of Greece, debts were built up based on dodgy accounting and bribes. Not done by the people but by a small group of corrupt politicians and lobbyists.
This documentery, called Debtocracy, is well worth watching. It looks at Ecuador as an example of how to audit debt and reduce what is owed by discounting odious or illegitimate debt.