International bank regulators gave a second dangerous incentive to banks to lend to these countries, by classifying the debt as a close proxy for money for liquidity-management purposes (or to give protection against the risk of a bank run).

BBC: The eurozone's borrowing costs may stay lethally high

The ex-chairman of HBOS has admitted the bank took on too much risk in the run-up to the financial crisis in 2008.

BBC: HBOS ex-chairman Lord Stevenson admits errors

Sir James Crosby quit as deputy head of the Financial Services Authority (FSA) amid embarrassing questions about risk-taking at the bank he used to run.

ECONOMIST: Bagehot

Without such risk-sharing, though, much of the euro zone could be one bank run away from meltdown.

ECONOMIST: Charlemagne

Japan's central bank governor, Toshihiko Fukui, has been heavily criticised for investing in high-risk funds run by Mr Murakami.

BBC: NEWS | Business | Top Japanese fund manager charged

With the latest technology, says Cho, the bank can measure the profitability of every branch employee and customer, mine its customer database and run sophisticated risk-management and credit-analysis programs.

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