You may have seen the recent police ads that run with the headline "Terrorism: if you suspect it, report it." Completely agree with the sentiment, guys, but I admit to being a little confused by some of your advice.
"Do you know someone," asks the advertisement, "who travels but is vague about where they are going?" Mmmm. My dad once drove down the wrong side of a dual carriageway in Brentford, but I think he was just fooled by a nearby turn-off to an arts centre. Frequently when I'm on the tube, a High Barnet train is diverted to the Edgware branch of the Northern Line, which does suggest some lack of awareness of destination on the part of the staff.
The ad continues to scare the bejesus out of the reader.
Anonymous, pay-as-you-go phones are, apparently, 'typical' equipment of the terrorist. Unfortunately, they're also the typical equipment of half the population of the UK. I sense some of the kind of cause-and-effect confusion that tends to dominate undergraduate philosophy classes here. The fact that al-qaeda prefer the flexibility of pay-as-you-go tariffs doesn't actually mean that pay-as-you-go users are likely to be members of al-qaeda.
The best question, however, is: "Do you know someone who visits terrorist-related websites?" From this, we can only presume there are people out there who know their friends to be would-be bombers, but have somehow managed to put it out of their minds or invent some innocent explanation for their mate's surfing habits. Now, confronted by the ad, they're scratching their heads. Maybe there was something odd about all that streaming of speeches from Osama bin Laden. Come to think of it, that last phone bill had an awful lot of calls to remote mountain regions of Afghanistan.