Kathryn Harrison

Joan of Arc was born 600 years ago. Six centuries is a long time to continue to mark the birth of a girl who, according to her family and friends, knew little more than spinning and watching over her father's flocks.

There are clearly many good politicians who are guided by religious belief, so the mix can work. But there's a line to be drawn. It would be hugely dangerous for a country's laws to be set by the scriptures, and particularly those of the expansionist religions.

Finding a 'sacrificial lamb' on whom to tag blame for complicated problems is an important instrument in the toolkit of politicians, because it deflects blame for the nation's economic woes away from their own regulatory lapses, economic mismanagement and coddling to labor unions.