Noah, over at Danger Room, hints at what I suspected Saturday, that the two "bombers" from Friday's botched attack on Glasgow's airport were the same men who planted crude car "bombs" at two points in London.
Bruce Schneier sums up why I call these attacks crude and not the deadly weapons some might want you to think:
...putting a propane tank into a car and driving into a building at high speed is the sort of thing that only works in old episodes of The A Team. On television, you get a massive explosion. In real life, you only get a small localized fire.In the movies, such an act results in a massive, extensive explosion; in real life you get localized fire.
That said, terrorism works with or without spectacular explosions and mass death. This was certainly not al Qaeda's finest. Had it been, they would have used some form of high explosives (as usual). TNT, et cetera, has a detonation velocity that is nearly an order of magnitude higher than an inefficient explosive such as propane and gasoline. The nails wouldn't have made it much farther than the exterior of the car.
I'll throw another suspicion out there: The latest attempts to make petrol, propane and nails into a MacGyveresque and amateur weapon were more of a repercussion from the knighting of Muslim poet Salman Rushdie than the usual offensive actions of al Qaeda proper.
Although I'm not entirely convinced of this yet.
[UPDATE] "So incompetent as to be almost laughable" is the way a former Scotland Yard detective spoke of the recent failed (to detonate) terror attacks in the United Kingdom. He also speculates that 'al Qaeda' should not be receiving credit for these attacks. TPM has the video, watch it: