(WORLD VIEW): Geography and history have left Afghanistan a fractured landscape, the contours of which are re-emerging as the United States withdraws from its 20-year engagement. Landlocked in Central Asia, Afghanistan has a history of being a geographically fragmented nation with an equally fragmented society, with concentrations of ethnic, sectarian and clan affiliations that have long shaped the Afghan context. After the U.S.-backed invasion in 2001, the country’s otherwise warring populace was temporarily brought together through a newly established Afghan government backed by the U.S.-led coalition. However, Washington’s latest decision to end its 20-year occupation threatens to tear the delicate threads preventing the country from once again descending into civil war….