It was a mere fleeting image amid all the others that were beamed into our living rooms on that momentous election night: 7-year-old Sasha Obama in her black party dress, bounding gleefully up into her father's arms, each in turn planting a happy kiss on the other's cheek. But the heart-tugging moment was as poignant a reminder as any that a vigorous, appealing young family is entering the White House - one that will bring a dramatically different energy and style to the presidency. And on that night, it wasn't hard to see why some have been tempted to make...