U.S. officials report no specific threats against the nation as the 9/11 anniversary nears. Still, Americans' nerves are on edge. news_military_planes_rts.jpg home Nation on Alert realonemusic.gif http://abcnews.go.com/sections/wnt/videofiles/Video/020909wnt_nation_video.ram 10316687357270 ABCNEWS Report - SuperPass lock_icon.gif audio.gif rtsp://demand2.stream.aol.com/cnn/audio/topstories.rm?rpurl=http://www.cnn.com/ 10316687357271 CNN Radio Report - Free lock_icon.gif lock_icon.gif big_headline