Now, a cursory examination would have shown it to be non-firing: one of the examiners was quoed as not knowing whether it could be, and was laughed at – but firing guns of such size are indeed made by hobbyists (though I suspect they are less dangerous than a ball-point pen), and a flare pistol of this size is widely available (and if fired at a person could possibly do quite a bit of damage).

But non-firing replicas are banned, for whatever reasons. Which raises the question of just what a “replica” is: something that actually appears to be the original, or anything that bears any resemblance? That (possibly phony story) T-shirt last week?

As far as know, there is no definition given to TSA and other screeners. Perhaps they could copy one from elsewhere: I used to own a replica imported from Japan, where collectors must use them rather than ANY real gun, and it came with a document from a Federal agency (I think FBI, not ATF) stating that i was a replica, not a weapon.