Every Churchill biography contains the story about the Duke of Marlborough who finally discovered how to use a toothbrush. Getting ready for bed, he brushed his teeth but nothing happened. No foam, no minty taste, no smooth clean surfaces. Nothing. Being a member of a class not known for its submissive patience, he hurled the toothbrush across the room and bellowed “Bloody thing won’t work!” Actually it worked fine as long as his valet squeezed out the toothpaste onto the brush for him. He had been doing this for years, but on this one night he forgot, leaving his master …