Personally, I think that having law enforcement that can't tell a bomb apart from a bunch of flashing LED lights is as bad as having a narcotics cop that couldn't tell cocaine apart from flour. I doubt anyone would notice if someone was carrying around "hoax anthrax" or "hoax nerve gas" (much less the real stuff), unless it was packaged in some ridiculous container worthy of a Hollywood movie. Given the Boston police's bomb identification accuracy record so far, one wonders if they need to hire different people, or at least invest some money into training.
Update (2007-09-23 12:28 +0800): I can see the argument that such training (or hiring) would be a waste of money—when the police misidentify something as a bomb, it doesn't cost too much if they don't do it too often, and the imagined downside in lives lost and PR for whoever runs law enforcement is large. So ignore, for a moment, the externalities involved in the police terrorizing and potentially killing (they claim in the news that they came close) citizens.
Is it conceivable that this seeming pattern of bomb misidentification is a sign that they might also misidentify a real bomb when they happen across one? Shouldn't they know how to tell what's likely to be a bomb from what's likely to be a pile of digital electronics so that they'd be able to call in the bomb squad or shoot to kill when they do find something that has more than a Maxwell's demon chance of exploding?
In the end, there's a continuum involved. Is it too many times if the police misidentify a bomb and spend the time and money to go through this whole exercise once a year? twice a year? once a week? three times a day? When does your personal perception switch from "They're just protecting us" to "That's incompetent?"
Update (Sep 23 13:35) Does Logan Airport have no better way to detect bombs than "look for the blinking LED lights and breadboard?" If they don't, isn't that the more frightening thing?
the undercover agents . . . brought knives, a bomb, and a gun in carry-on baggage through several checkpoints at different terminals without being stopped
The slashdot discussion includes a wide range of interesting opinions (hidden among the usual crap).