The people who set off the bombs in London may have expected to get away:

one police hypothesis is that the bombers were tricked by a "master" who told them they would have time to escape - when in fact the devices were set to go off immediately.

"The bombers' masters might have thought that they couldn't risk the four men being caught and spilling everything to British interrogators," an unnamed security official told the Telegraph.

Lending weight to the theory is the fact that all four men had paid up their parking tickets before boarding a train at Luton for King's Cross, and that they all bought return tickets to the capital.

Moreover, the paper said, the men were carrying their explosives inside rucksacks, as opposed to strapped to their bodies as is common practice among suicide bombers.

None were reported to have cried "Allah Akbar" (God is Greatest) before setting off their charge - something which most Middle Eastern suicide bombers do.

If they were duped into it, as it looks like might be the case, it will make it harder for future recruitment, because bombers unwilling to sacrifice themselves may not trust their masters. Of course, this isn't unprecedented. Bin Laden joked on the videotape about many of the September 11 hijackers having no idea why they were hijacking the planes.

It would be of a kind with the reports that some car bombers in Iraq are chained/tied to their steering wheels & the explosives detonated remotely, just in case the bomber gets cold feet.

If it turns out to be the case, though, this'll probably be just one of those things the fanatics throw down a memory hole, since it doesn't fit their worldview. Sort of like the rumors that bin Laden had his mentor, Abdullah Azzam, assassinated by car bomb in a kind of Mob hit to enable OSB to take over control of al-Qaeta.

There are two possibilities:

1. the bombers went ahead with the full knowledge they would die, and paid for the round trips and parking just to avoid premature notice.

2. the bombers were so stupid as to believe that, contrary to almost universal experience, they were going to be allowed to plant the bombs and run.

I'm going with 1.

> If they were duped into it, as it looks like might be the case, it will make it harder for future recruitment, because bombers unwilling to sacrifice themselves may not trust their masters.

Don't bet that they "won't get fooled again".

Speaking of not getting fooled again, reports of today's incident included this snippet:

"He said that a man was carrying a rucksack and the rucksack suddenly exploded. It was a minor explosion but enough to blow open the rucksack," McCracken said. "The man then made an exclamation as if something had gone wrong. At that point everyone rushed from the carriage."

More rucksack bombs, and more people carrying them surprised that they're going off in their hands.

They're not calling today's incident a copy-cat yet, and they're not saying that it was from Al-Quaeda, either. But it looks like a very similar M.O.

I just thought more about it. The rucksacker could have also been surprised or upset that the explosion wasn't larger than it was. I guess that, without knowing exactly what the man said, it's impossible to say.