Ethnic Cleansing not US Troop Surge real cause of reduced violence in Iraq

A new study published from the University of California gives evidence of the real reason peace has begun to settle in many parts of Iraq. And much to George Bush and John McCain's dismay, it has nothing to do with the US troop surge in 2007.
http://news.yahoo.com/story//nm/20080919/sc_nm/iraq_lights_dc

WASHINGTON (Reuters) – Satellite images taken at night show heavily Sunni Arab neighborhoods of Baghdad began emptying before a U.S. troop surge in 2007, graphic evidence of ethnic cleansing that preceded a drop in violence, according to a report published on Friday.
The images support the view of international refugee organizations and Iraq experts that a major population shift was a key factor in the decline in sectarian violence.
"By the launch of the surge, many of the targets of conflict had either been killed or fled the country, and they turned off the lights when they left," geography professor and study lead John Agnew of the University of California Los Angeles.