This is just the point that I was thinking of when I heard about potential exemptions based on people's status. If some people get security exemptions, then I would expect attempts at bribery or blackmail to get those people to act as "mules".

Consider that the IRA recently managed to rob a bank in Northern Ireland by taking hostage the families of two senior managers at the bank and then getting those two guys to allow the robbery to take place. I think this shows that if a person's family is under threat he can be coerced to do some pretty dire stuff. (OK - so a bloodless bank robbery is not in the same league as a hijacking).

If pilots became exempt from the security check, how far fetched is it to imagine that a terrorist organization would use this kind of tactic to force a pilot to take a prohibited item into the airside zone and leave it there for someone to use on another flight?

For this reason, I think there should be no exemptions. By all means give pilots, senators, VIPs and morris dancers a priority lane or something - but make sure that they are screened as thoroughly as everyone else. To do less could put their families at risk.