New information from France and Britain make clear that the al-Qaeda mail-bomb plot intended to attack jets in mid-air and not necessarily the locations to which the packages were addressed.  France’s interior minister told the media that the bomb discovered in the jet in East Midlands, England would have detonated in 17 minutes, a finding confirmed by CBS through its British sources:

France’s interior minister says that one of two mail bombs sent from Yemen last week was defused just 17 minutes before it was set to explode.

Brice Hortefeux provided no other details in an interview Thursday on France’s state-run France-2 television, nor did he say where he got the information about the timing.

When investigators pulled the Chicago-bound packages off cargo planes in England and the United Arab Emirates Friday, they found the bombs wired to cell phones. The communication cards had been removed and the phones could not receive calls, officials said, making it likely the terrorists intended the alarm or timer functions to detonate the bombs, U.S. officials have said.

A British counterterrorism source tells CBS News it was the bomb found on a plane at East Midlands airport, in England, that was defused just minutes before it was set to explode.

ABC reports that although the bombs were wired to cellphones, the detonation would not have been remotely controlled by AQ.  The terrorists used the alarm clock functions instead as a timer:

The plotters behind last week’s unsuccessful mail bombings could not have known exactly where their Chicago-bound packages were when they were set to explode, even after a suspected test run, U.S. officials say.

The communication cards had been removed from the cell phones attached to the bombs, meaning the phones could not receive calls, officials said, making it likely the terrorists intended the alarm or timer functions to detonate the bombs.

“The cell phone probably would have been triggered by the alarm functions and it would have exploded midair,” said a U.S. official briefed on the investigation of the bombs taken off cargo planes Friday in England and the United Arab Emirates. This person, like other officials in this story, spoke on condition of anonymity to discuss the case.

This became more clear over the weekend.  Although at least two of the packages were addressed to synagogues, the existence of timing mechanisms strongly indicated that the addresses were secondary, and perhaps just used to send a message after the actual attacks had occurred.  There are easier ways to send actual letter bombs, which activate not on timers but mechanical detonation from opening the letter or package.

If the attack targeted the planes themselves, then cell phones wouldn’t work reliably, either, not unless the jet was low enough to pick up cell tower coverage.  Using them as timers makes more sense; the clocks are reliable and AQ already has plenty of experience in using cell phones in IEDs.  While the terrorists would have no way of knowing precisely when the packages would be airborne, a shotgun approach to the plot would almost ensure that at least a few would detonate mid-air.

The Obama administration wants to start changing rules on cargo handling in response to the plot:

The Obama administration, which has been monitoring intelligence on possible mail plots since at least early September, was preparing new security rules for international cargo in response to the attempted attack.

Security officials are considering requiring that companies provide information about incoming cargo before planes take off, one U.S. official said. Currently, the U.S. doesn’t get that information until four hours before a plane lands.

A second official said the U.S. will also expand its definition of high-risk cargo, meaning more cargo will be screened from countries known as hotbeds of terrorism.

While these will add delays and costs to shipping — which had to have been one of the goals of the AQ plotters — they seem to be both sensible and necessary.  In retrospect, one might wonder why these controls weren’t adjusted years ago, but until now AQ has always attacked passenger systems.  Their shift in targets indicate that we have succeeded in making those attacks more difficult and forced them to find easier targets.  Thankfully we had the chance to react and adapt before people died.