The original "air marshals" were an invention of the Nixon administration. They were so useless that they were disbanded, with most of them going to BATFE (IIRC.)
So Bush resurrected them following 9/11.
Actually, there have been many more arrests of Federal air marshals than that story reported, quite a few for felony offenses. In fact, more air marshals have been arrested than the number of people arrested by air marshals.
We now have approximately 4,000 in the Federal Air Marshals Service, yet they have made an average of just 4.2 arrests a year since 2001. This comes out to an average of about one arrest a year per 1,000 employees.
Now, let me make that clear. Their thousands of employees are not making one arrest per year each. They are averaging slightly over four arrests each year by the entire agency. In other words, we are spending approximately $200 million per arrest. Let me repeat that: we are spending approximately $200 million per arrest. --Cong. Duncan
Schneier's blog also has this:
People intent on preventing a Moscow-style terrorist attack against the New York subway system are proposing a range of expensive new underground security measures, some temporary and some permanent.
Wrong move, he says, and wasted money (just like "air marshals.")
...What all these misguided reactions have in common is that they're based on "movie-plot threats": overly specific attack scenarios.
A far better strategy is to spend our limited counterterrorism resources on investigation and intelligence - and on emergency response. These measures don't hinge on any specific threat; they don't require us to guess the tactic or target correctly. They're effective in a variety of circumstances, even nonterrorist ones.
The result may not be flashy or outwardly reassuring - as are pricey new scanners in airports. But the strategy will save more lives.Yup.