In the security line at the airport, you whip out your liquids, laptop and keys and throw them in a plastic box. You take off your jacket and fling it and your purse into a box; you take off your shoes. You know that putting things in boxes could make it easier for someone to grab them, so as you step through the machine that searches you, you eye the boxes rattling over the conveyor belt. If you’re not stopped, you lunge for your property.

If you’re like me, there’s a burst of annoyance just before you reorganize things and breathe easy. Is all this really necessary, you wonder, or is it theater designed to remind us that there’s a war on terror and the government is our protector?

Not many of us are so given to anti-government conspiracy theories as to believe that. But two cases in five months in which people who never should have been allowed on planes boarded them while millions of us had to go through this welter raise everyone’s irritation level. We all have our stories of being stopped for something, or for nothing.

Checking in for a flight to Warsaw a few years ago, I was stopped briefly as an alert Polish desk clerk asked why I only had two rather small bags for a month’s stay. But last Christmas, a Nigerian whose father actually warned American authorities that his son was becoming an extremist got on a plane from Amsterdam to Detroit with only a carry-on bag—and tried to set off an incendiary device.

And while some Americans are held up at airports because they marched in anti-war rallies or criticized the government, a man linked to a car bomb smoking in Times Square May 1 was barely caught before his plane for Dubai left the gate. (What about those all-points bulletins we see on TV crime shows that would have stopped him at the desk?)

In 1997, before the fear of terrorism became a constant in the U.S., I was stopped by El Al staff on a flight to London because I had paid for a separate ticket to hop over to Poland just for two days. The questioning was courteous and the El Al staff were easily satisfied, but clearly alert for anything that appeared odd. That encounter with El Al, which maintains an impressive safety record despite a constant terrorist threat, seems instructive now.

Airport security expert Robert Poole says the U.S. should think like Israel, concentrating on weeding out “bad people” rather than treating all passengers as though they presented an equal threat. The key to Israel’s success, he says, is not rifling through travelers’ belongings but watching them carefully, providing airline staff with constantly updated intelligence, and training them to take it seriously.