The gentle essayist E.B. White once wrote of his dog Fred that he pursued each day “with the complete conviction that through vigilance and good work all porcupines, all cats, all skunks, all squirrels, all houseflies, all footballs, all evil birds in the sky could successfully be brought to account and the scene made safe and pleasant for the sensible individual–namely, him. However distorted was his crazy vision of the beautiful world, however perverse his scheme for establishing an order of goodness by murdering every creature that seemed to him bad, I had to hand him this: he really worked at it.”

Fred is weighing on my mind because of a story that has received very little publicity here: In early December, some knuckleheaded police at Paris’s Charles de Gaulle Airport planted a packet of plastic explosives in an innocent passenger’s suitcase, “chosen at random.” It was part of a training exercise for an equally knuckleheaded bomb-sniffing dog. The dog flunked the test, the suitcase went skittling down the conveyor belt, and it was apparently loaded onto a plane destined for parts unknown. The police are still looking for the dark-blue bag: “We hope the person who finds this will take it to the local authorities…. We hope they don’t throw it away.”

If ever there was an object lesson illustrating the need both for sane oversight of security measures and for the vigilant upholding of civil rights and liberties, this would have to be it. Since at least three of the planes upon which the missing bag might have been placed were headed to the United States, I can’t help musing about it as some kind of cross between great law school hypothetical and bad action movie: How many tort cases? Let me count the ways…

The explosives didn’t have a detonator so “are not thought to pose a danger” but if detonated “would probably be enough to blow a door from a car.” So question number one: Why haven’t all air carriers reinforced baggage compartments to make them relatively bombproof (as has El Al, with life-saving results)? And while we’re thinking about it, why not reinforce cockpit doors rather than just handing pilots guns? But that’s been asked before, and I guess it comes down to money, and airlines don’t have any and Congress isn’t about to subsidize anything so constructive, not while the Punxsutawney Groundhog Museum and the Rock and Roll Hall of Fame need porky embellishment.

But looking on the bright side, the bomb didn’t explode. Or hasn’t yet. So I’m trying to imagine what the average Joe would do if he opened his suitcase and found a “mobile-phone-size lump of plastic explosives” therein. Would the ordinary lay person even know what it was? Would it be unreasonable for said person to dispose of it as mysterious trash, to toss it down the incinerator in a large building, say, or perhaps leave it lying unnoticed at the bottom of a suitcase, under the bed or in the back of a closet, till a hot summer day warmed it up? Would the children in the family enjoy tossing it around like a ball? If you were not an American citizen, unable to account for its presence in your possessions, would you not be very, very frightened of bringing it to suspicious authorities, even assuming you did have an inkling of what it might be?

The whole episode is an unfortunate setup for more talk-show sneering at all things Gallic, but there is no border for disastrous human miscalculation. It makes me long to know what kinds of training exercises are employed not just in France but here at home. If we the ordinary people cannot know everything about such training, it would be very nice to be reassured about what kinds of oversight mechanisms are in place. As a culture of secrecy and a habit of anything-goes settles over the “war on terror,” the failure to hold police, soldiers and spies to the highest levels of accountability can only enhance the likelihood of stupid–really, really stupid–mistakes.

The possibilities grow yet more theatrical if one imagines what might have happened if the totally unsuspecting owner of the blue suitcase in question had collected it at his destination, only to be sniffed out by better-trained, more highly professional hounds at the receiving end. Surely carrying plastic explosives aboard an international flight would get you instant casting as a terrorist or an enemy combatant. And then you might just disappear. You might be detained indefinitely. Guantánamo? A military brig? Were you under the impression that they have to tell? Recent suits challenging conditions in detention centers for illegal immigrants, moreover, indicate that there might be a few long-toothed, hyped-up hounds sauntering about such a prison, with more on their minds than mere sniffing. The degree to which one could appeal to domestic courts to challenge or appeal your detention would be in question. Your access to a lawyer would be limited. Your ability to know the evidence against you would likely be constrained. Somebody might be good enough to tell you that the Supreme Court is working on the question of how much due process you deserve, but you wouldn’t want to hold your breath.

Assume also that, as the authorities are snapping on the cuffs, they never link your presumptively evil terrorizing threat of a self to the teensy bureaucratic snafu in a distant little land peopled by effete, funny-speaking, liberal friends of Mr. Kerry. How you might regret that you put off writing that check to the ACLU.

Finally, just for fun, let’s assume that the French police didn’t even realize that they’d lost the little lump of explosives, for, like E.B. White’s dog Fred, they “had no contemplative life, but…held as a steady gleam the belief that under the commonplace stone and behind the unlikely piece of driftwood lay the stuff of high adventure and the opportunity to save the nation.” (In reality, the gendarmes would have us know that the whole affaire resulted from only a tiny “error of surveillance for ten seconds or a little more.”) But errors of surveillance come in all sizes; some go on for ten years, or possibly forever. That’s why we have habeas corpus. At least that’s why we used to.