The reaction to the shooting death of Rigoberto Alpizar provides a sobering glimpse into America's current obsession with keeping ourselves safe from terrorism. Alpizar was shot by federal air marshals after he ran off a plane that was about to depart from Miami to Orlando.

Initially, authorities claimed that Alpizar was yelling that he had a bomb as he ran down the plane's aisle with a backpack strapped across his chest. Yet the Orlando Sentinel interviewed seven passengers who claimed Alpizar wasn't saying anything at all, let alone yelling about a bomb, while no passenger backed the government's story.

Alpizar turns out to have been mentally unstable and altogether harmless. It's of course possible that Alpizar claimed he had a bomb once he was out in the jetway, but it's also possible that the two air marshals who shot him panicked, and concocted the story about a bomb after the fact, to make their tragic mistake of shooting a harmless mentally ill man seem like a justifiable use of lethal force.

Or perhaps Alpizar was suffering from a delusion that there was a bomb on the plane, and the marshals misunderstood something he said in the jetway. The ongoing investigation of the incident will no doubt produce more details, but one thing is already clear: the disturbing eagerness with which the government and the media rushed to judgment in this matter. Within hours, White House spokesman Scott McClellan was proclaiming that the shooting was justified, despite the haziness of the factual situation.

This was hardly surprising, but what was disappointing was the markedly deferential attitude the media took toward the government's hasty assertions that the air marshals acted properly, even after major discrepancies began to appear between the government's initial story and the emerging facts. This deference was all the more striking given that less than five months ago the British police released what turned out to be a wildly inaccurate story about a man who they had just shot to death on the subway, in what later came to look like a case of something not too far removed from cold-blooded murder.

Indeed, some of the media commentary on the day after the shooting treated the incident not as sobering tragedy, but as an encouraging sign that the system is working. One guest on a cable news show devoted to analyzing the stock market went so far as to recommend airline stocks, on the theory that Americans would be reassured that an apparent security risk could so readily elicit a lethal reaction from those entrusted with keeping us safe.

A comment posted on the Orlando Sentinel's Web site reflects a similar sentiment: "The lesson here for all of us is this: we have to take responsibility for our family members and ourselves. If you act in an unsafe manner, you may very well be shot. I am OK with the terrorists understanding this lesson."

The attitude reflected in this comment illustrates what most if not all of the elaborate security rituals that have been enacted since 9/11 are really about. These rituals don't actually make Americans appreciably safer (who believes that a real terrorist would behave in the manner Alpizar did?), but they make many of us feel safer.

What all the security protocols, and color-coded threat levels, and air marshals who are prepared to shoot people who act strangely are designed to achieve is to create the illusion of competence and control. The authorities know what they're doing _ this is the essential message. And if innocent people end up getting spied on or imprisoned or tortured or shot, well that's just a cost of what our government likes to call freedom.

(Paul Campos is a law professor at the University of Colorado and can be reached at Paul.Campos(at)Colorado.edu.)