SUJATPUR, Bangladesh (Map, News) - Everyone knew it was out there somewhere, an invisible line that cut through a cow pasture and, at least in theory, divided one nation from another. But no one saw it as a border - it was just a lumpy field of grass, uneven from the hooves of generations of cattle, and villagers crossed back and forth without even thinking about it. Today, no one can ignore the line. In a construction project that will eventually reach across 2,050 miles, hundreds of rivers and long stretches of forests and fields, India has been quietly sealing...