IMHO,

If trained properly, an interviewer can gain a great deal of information from questioning a passenger and then decide if additional screening is warranted. I have never been off of North America, so I do not have first-hand experience with El Al. But from everything I have read and heard, their security is very effective. I realize that the volume of passengers in the U.S. is far greater than the volume in Israel, but some of the Israeli security practices could be adopted here. If nothing else, using behavioral profiling/interviewing along with current TSA screening would address many of the criticisms that TSA passenger screening is just a dog and pony show. The key is training.