As a uniquely American genre, westerns have traveled a long and dusty trail since John Ford’s My Darling Clementine. In John Hillcoat’s The Proposition, the trail winds its way to the Australian Outback. Brutal yet brilliant, beautiful though bloody, the screenplay by Aussie rocker Nick Cave (The Bad Seeds) holds true to the elements of the genre: Symbolic of all things good is the woman from the east, a fight for survival and power against......