Listening to the 9/11 ceremonies on NPR, the spare amounts of speechifying and the moments of silence reminded me of what is called mokutou (黙祷) in Japanese, or "silent prayer."
Although religious in origin, mokutou is unadorned by religious trappings. When it comes to memorials, the sparer the better (Bloomberg was also right to keep the ceremonies mostly secular).
In a strange, cosmic coincidence, 9/11 was the sixth month anniversary of the earthquake and tsunami that devastated Northern Japan on 3/11. Here is a clip of a first month mokutou.
The "mokutou" is always announced, though it's usually preceded by a chime, not a siren. (The reason for the press attention in this particular case is ex-Prime Minister Hatoyama, third from right).
A simple ritual can displace a lot of empty rhetoric. The basic form of kiritsu (stand) and rei (bow) permeates Japanese society, and sort of substitutes for the Pledge of Allegiance in public schools.