Oliver Stone's treatment of 9/11 in "World Trade Center" drew a mixed reception ahead of its European premiere at the Venice Film Festival on Friday while Spike Lee's look at post-Katrina New Orleans, "ground zero" of America's biggest natural disaster, was applauded. Booing countered by applause rang out at the end of Stone's account of a true story of the heroic survival of two policemen who were trapped in the rubble of the Twin Towers for 24 hours. Spike Lee's "When the Levees Broke: A Requiem in Four Acts" won warm applause when the four-hour documentary about Hurricane Katrina spooled to a conclusion. Shown on the anniversary of the hurricane in a city which has long faced the same flood risk as New Orleans, the movie provides a detailed chronology of events through the eyes of survivors and documents the anger of America's black underclass, the real victims of Katrina, at government inaction. Denis Barnett reports.