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New Air Rules: BYOB?

As far as I can tell the revised rules are good for drug stores and slightly better for air travelers. But, it's hard to determine whether it does anything to change our vulnerabilities to liquid explosives one way or the other. Better? Worse? Who knows?

After Scotland Yard busted the UK liquid bomb plot in August, US officials moved immediately to crack down on mascara, mouthwash, and shampoo.

It was prudent, security analysts argued, because terrorists could use carry-on liquids to construct bombs on board. Since explosive components could be hidden inside shampoo bottles or hair gel tubs, and considering some common cosmetics, like nail polish remover, can actually be used themselves in a bomb making recipe ALL liquids and gels were banned.

Passengers threw away perfume, liquor, and their double lattes or they jammed all of their toiletries in CHECKED bags. Checkpoint lines moved smoothly as passengers carried far fewer bags, but explosive scanners in airport basements were quickly overwhelmed by a whopping 20 percent increase in checked luggage.

But, somehow the system and its two million passengers a day got used to the ban. And now it's changing.

Beginning tomorrow passengers CAN carry on most of the toiletries they need as long as they're in miniature three ounce bottles and tubes. I can see the lines forming now at the 99 cent bargain bins at CVS.

And coffee drinkers can rejoice. The four dollar cappuccinos sold on the safe side of the metal detectors will once again be permitted on airplanes.

The Department of Homeland Security says the changes come in response to a new analysis of the threat presented by liquid explosives. Three ounce carryon items are too small to present a real hazard and the stuff passengers buy inside an airport's "sterile area" has already been checked.

All of this, though, tends to camouflage a significant on-going problem. Al Qaeda has been experimenting with liquid bombs since the mid 90s and US airports currently have little available technology to detect them. Research and development on explosive scanners remains years behind and, under the most optimistic scenario, it will be months if not years before effective and efficient liquid bomb detectors are deployed in most US airports.

So the overarching liquid carry on ban remains in effect…with a few small three ounce tweaks…as officials struggle to balance security and commerce against a threat we're not equipped to defeat.