A chain of evidence that investigators believe will help convict Saddam Hussein begins at a windswept grave in the desert near Hatra, in northern Iraq. The burial site – a series of deep trenches that held about 2,500 bodies, many of them women and children – is one of many mass graves that dot the country. But it was the first excavated by an American investigative team working with a special Iraqi tribunal to build cases against Mr. Hussein and others in his government. Full Story