Regarding the London bombings: with the general assumption of al-Qaeda links
and TV commentators expressing surprise that two of the bombs were let off
in areas with a high Muslim population, it seems to me that the explosions
were designed to cause as much long-term disruption to the tube network as
possible, rather than targeting (or avoiding) specific types of people:

- Edgware Road caused the loss of three lines (or parts of): District
(Edgware Rd branch), Circle, Hammersmith & City.
- Aldgate similarly caused the closure of three lines: Circle, Hammersmith &
City, Metropolitan.
- Kings X was located at the Picc Line reversing point, thus causing two
sections to be closed: Arnos Grove to Kings X, and Kings X to Hyde Park
Corner. Had the bomb detonated a couple of stations either side of Kings X,
it would have presumably been possible to keep one of the two sections
running.

This would certainly mean precision timing and therefore significant prior
research, suggesting that the perpetrators were home grown. Where the bus
explosion comes into all this is open to question. Maybe the bomb was indeed
meant for another tube line but didn't find its target for whatever
reason(s). If so, one can only begin to guess where it might have been
intended for. Another location radiating from Kings X?

Perhaps this is giving those responsible for the carnage too much credence
and the only reason those locations were chosen is that they proved to be
the easiest routes on which to leave an item unattended without detection or
suspicion.

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