[B Knotts]

In addition to the obvious idiocy of diverting a flight because someone left a box cutter on the airplane (hint: no one will ever successfully hijack an airliner with a box cutter for the next 20 years, at least), this also points out how stupid the banning of nail clippers and plastic knives is.

We don't even know that the hijackers brought their "weapons" through security. It is entirely possible that their box cutters were placed onboard through this very channel (caterers).

But, all this crap is just for show, anyhow. Don't think we don't know that. If they were serious about stopping terrorists, they'd let the pilots arm themselves and they'd let CCW holders carry onboard with frangible ammo.

[boltfromblue]

People with CCW might like to take the training for air marshal, in the event they can act as subs, if not become marshals. Pilots might, too, for their dead travel time.

[weegee]

Regarding other people planting weapons on the planes that were crashed...

I don't think that this was the case because the letters the hijackers had reminded them to bring their knives.

With increased scrutiny at security checkpoints, assistance from ground crews becomes more likely though.

And then there are all of the businesses that operate between the metal detectors and the boarding gate. Most probably have some cutting implements (restaurants, newsstands, gift shops) for use by the employees if not the customers.

If you are really determined, an aluminum can (from the beverage cart on the plane) could be torn into a sharp edge.