Since the attempted "underwear bombing" a few days ago by a Nigerian Muslim, it has suggested more than ever that the US begin using some form of passenger profiling, rather that absurd levels of checkpoint screening and behavioral restrictions, to prevent future attacks. The model is Israel's security system, which despite the presumed high motivation of terrorists has not suffered a successful attack in decades (since the current system was set up).
I generally think that it's worth preserving the lives of many people even at the cost of the convenience or feelings of a few people, and thus, you would expect that that I would support the use of a profiling system in the US. But there are two reasons why I hesitate.
First, the Israeli airport security checkers ask passengers a variety of questions, and try to ascertain from a person's emotional responses whether they have hostile intentions or something to hide. Such a determination must take a lot of intelligence and training to be done accurately. TSA personnel in the US do not have a reputation for this kind of competence, and to hire or train people to do this for all US passengers (many more than in Israel) would be incredibly expensive.
Second, in addition to the psychological methods, I'm sure Israel also profiles people based on their origin. I occasionally hear reports of Arabs who say they have been questioned for hours in an aggressive and humiliating manner at Ben Gurion airport. While the reliability of any single report may be doubted, I am sure Arabs in general get more heavily scrutinized than Jews. Anyway, this method works because there are really only two, relatively homogeneous populations in Israel: Jews and Arabs. The US has much more diverse populations of both "suspicious" people (i.e. Europeans or blacks who converted to Islam) and "non-suspicious" people (i.e. Hindus or Sikhs). So profiling (which can be ineffective if done wrong) would be harder in the US than Israel. Not useless, but significantly harder.
In short, I don't think it will be easy for the US to design a system that works as well as Israel's. That said, some easy things can be done, like not aggressively checking grandmothers and babies. I don't think a terror attack has ever been committed by an old lady in a wheelchair and, in all honesty, there's no reason to think that such attacks would start now.