Most definatley the war. Even if you turn off the TV and try to ignore the whole situation....you still end up hearing about it.

The runnerup would definatley be the tragedy of the Space Shuttle Columbia. I live close to Johnson Space Center in Texas. The community took it rather hard, because that area of Houston takes great pride in NASA. Many people work for Nasa and it's contractors (Lockheed Martin and Boeing) And many astronauts (including former astronauts Neil Armstrong and Micheal Collins as well as astronauts on Columbia) live/or formerly lived in the area. I will always remember going to the gate of Johnson Space Center and adding some flowers to the makeshit memorial. And I also remember people crying, putting up signs of respect, lighting candles,as well as the presence of the media for a couple of weeks after the event. The tragedies of Apollo 1, Challenger, and Columbia will never be forgotten.