DUBYA LATER South Sudanese president Salva Kiir, wearing a cowboy hat given to him by former president George W. Bush in 2005, arrives to celebrate the formal proclamation of his country’s independence Saturday. Bush was a major proponent of South Sudan’s statehood, helping broker an agreement between Sudan’s central government and rebels that allowed the southern part of the country to secede. (Photo: Tyler Hicks / The New York Times)