This is favouring the market leaders most, says Heidi Gardner of Harvard Business School, because the crisis has made governments risk-averse about whom they hire.

ECONOMIST: Professional-services firms

During the relatively modest downturn at the start of this decade, for example, many professional-services firms cut too deeply, especially in their lower ranks, and found they were poorly positioned when strong growth resumed sooner than expected, says Heidi Gardner of Harvard Business School.

ECONOMIST: Human capital and the crisis

Intriguingly, the voucher debate has pitched civil-rights-era black leaders and teachers' unions, who oppose the idea, against supporters ranging from the conservative governor of Florida, Jeb Bush, to the leftist head of the Milwaukee school board, John Gardner, a labour organiser who once led a campaign to support Cesar Chavez, the founder of the migrant farm-workers' union.

ECONOMIST: Sorting out school choice

He went to college at Southern Utah University, where he was a running back on the school's football team and graduated with a degree in political science in 2001, the school's athletic department spokesman Neil Gardner said.

CNN: Notorious company: Dorner a 'friendly guy' gone bad

Milwaukee also suggests vouchers can be a competitive spur: in April, supporters of the city's voucher programme, led by Mr Gardner, won a bitter election to seats on the school board.

ECONOMIST: Sorting out school choice

Gardner had the same reaction when she handed him the note at school the next day.

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