(This post written in the departure lounge for my return flight from London to San Francisco, about 2am Pacific Time, and posted upon my arrival home.)

Security specialist Bruce Schneier uses a particular term to refer to the practices that are highly visible but ultimately of little value: "security theater." One of the canonical examples of security theater is the requirement that one remove one's shoes at the airport, or more recently, the 3 ounce limitation on liquids carried on-board a plane. These are demands that have little practical effect, but -- in large measure by inconveniencing travelers -- they give the appearance of doing something about aircraft security.

Today, just about fifteen minutes ago, I saw the normal level of security theater taken to new heights.

In the past, my flights to London have been on British Airways; this time, for a variety of reasons, I gave Virgin Atlantic a try. The SFO to LHR leg was generally pleasant, at least as pleasant as trans-Atlantic flights can be (i.e., I was constantly feeling guilty about the carbon footprint of my flight). The security theater in San Francisco was perfunctory and reasonably efficient.

Heathrow proved to be a different story. For whatever reason, the initial x-ray screening went more slowly than at SFO; moreover, the inevitable shoe-removal was actually a second line & screening, rather than just part of the initial pass-through. It turns out that this wasn't the end of it, however. Upon arrival at the departure gate, I discovered that Virgin has put together yet another security screening, requiring me to:

• Allow the screener to poke through my carry-on bag. Given what later transpired with the laptop, I was surprised that he didn't seem particularly interested in my unusual-appearing camera or multiple mobile phones (the woman being grilled next to me spent much of her time struggling to remove the battery from her lone mobile).
• Open and drink from the bottle of soda I had purchased from the vendor around the corner from the gate (and well-within the departure area).
• Remove my shoes again, so that the screener could... well, all he did was lift each boot. I'm not sure what that told him, other than I have reasonably lightweight boots.
• Open up my laptop screen so that he could run his fingers across the keyboard. He didn't care whether the laptop was on or off, or whether it worked -- just that the keys moved.
• He then told me to remove the battery. I told him no, that I needed to shut the machine down first so that I didn't lose data. I felt perversely amused that the laptop seemed to take three times longer than usual to shut down. Once the laptop had finally shut down, and I had removed the battery, all he did was look into the battery slot for about a second, if even that long. "All clear."

When I said that this all seemed rather absurd, given that I'd just gone through a screening a short while before, he sniffed that this was being done because I was flying to the United States, and that required extra precautions. I asked if British Airways was doing this, too, and he said that he hoped so -- but when I said that they weren't when I flew just a few weeks earlier, he just shrugged.

This wasn't done to me as a special random (or lone-male) screening. Every passenger on the 747 received this treatment. Given the screener's replies, I have no reason to believe that this was a just-added layer of security in response to a new threat.

Okay, I understand that, on the grand scale of things, this is at worst an inconvenience. But in many ways, it's the perfect illustration of just how brain-dead the current security model has become. This is all about going through ritualized motions without any actual utility. It's cargo-cult security.

And that makes it dangerous. To the extent that flyers -- citizens -- believe that this kind of time-consuming and vaguely humiliating inspection (the crotch-grabbing pat-down really should have a safeword) actually makes the flight safer, they're less-likely to pay attention to their surroundings. Someone who decides to do something evil on the flight has a greater chance of being successful, simply because passengers are made to think that the security theater actually made a difference.

The combined self-interest, awareness and reason of the public is our greatest source of defense against the unthinkable. This is true whether we're talking about human-caused or natural disasters. Anything that mutes these defenses without offering compensating benefits works to our ultimate detriment.