A new study out of UCLA has concluded that ethnic violence — not the Bush administration’s surge — was the primary factor in reducing violence in Iraq. UCLA geographers studied how much light was being generated at night in different neighborhoods of Baghdad. Night light in neighborhoods populated primarily by embattled Sunni residents declined dramatically just before the February 2007 surge and never returned. Meanwhile, the use of lights at night remained constant or increased during the surge in largely Shiite neighborhoods. Co-author Thomas Gillespie said, “If the surge had truly 'worked,' we would expect to see a steady increase in night-light output over time. Instead, we found that the night-light signature diminished in only certain neighborhoods, and the pattern appears to be associated with ethno-sectarian violence and neighborhood ethnic cleansing.”