I have been following these thread without comment so far, but here's my opinion. It seems like Mr. Bigley's death has had a profound emotional impact on people, because it seems like it has become a symbol of something bigger (the tragedy of this war, anger at Blair) ... so a minute's silence seems appropriate. It's difficult to make comparisons between people's emotions at events like 9/11 and this, and I don't think comparisons like that are necessary - just the fact that so many people are upset about the murder of Mr. Bigley justifies having a national moment of mourning.