On April 17, 1986, Anne Murphy was arrested at London's Heathrow Airport when the large bag she had been intending to send on her El Al flight to Tel Aviv was found to contain a false bottom in which a bomb had been secreted. The unwitting Murphy - or more accurately and relevantly, her fiance - didn't stand a chance of smuggling those plastic explosives on board. Her ticket had been purchased only a few days before the flight, immediately marking her as a passenger worth singling out for close attention by Israeli security. She had never been to Israel before and was flying alone - further red flags. Cursory questioning at the airport established that the fiance was a Jordanian-born man named Nezar Hindawi, who had told her, however implausibly, that he was traveling to Israel by a different route and would meet up with her there. That information ignited furious security concerns - here was a young, naive, Irish woman, who also happened to be pregnant with Hindawi's child, traveling alone to Tel Aviv, sweetly trusting that her Arab fiance would be joining up with her soon afterward. Her luggage was subjected to the most thorough of searches, the bomb discovered, and the jumbo jet load of El Al passengers saved. Hindawi, who had ruthlessly dispatched his own fiancee and unborn child to their deaths, was arrested the next day, and the bomb plot ultimately traced back to Syria. Hindawi was jailed for 45 years and London severed its diplomatic relations with Damascus. Israel's passenger-profiling airport security precautions had dramatically proved their life-saving value. PUBLICIZED SUCCESSES such as the Hindawi affair, along with innumerable interceptions that have attracted less attention, have garnered Israel a peerless reputation for air security, and led many Israelis to ridicule other countries' efforts in the field. That the security apparatuses of the United States and the rest of the West largely eschew passenger profiling is often ridiculed here. The aversion to singling out passengers of Middle Eastern origin, before and even after 9/11, in order to avoid allegations of racial discrimination is widely seen as political correctness gone dangerously overboard. No, of course not all Muslims are plane-hijacking terrorists. But most plane-hijacking terrorists, and most would-be plane-hijacking terrorists, are Muslims. Subjecting toddlers and grandmothers to the same security regime as passengers statistically more likely to constitute a danger seems, from an Israeli perspective, to be a misallocation of resources that places passengers at unnecessary risk. Which brings us to the recent dramatic arrests in Israel of two new immigrants, one from the US and one from the former Soviet Union, allegedly responsible, respectively, for a horrific series of acts of terrorism and for the gravest multiple homicide in Israeli history. Ya'acov Teitel, who made aliya from the US in 2000, had been arrested here three years earlier on suspicion of involvement in the murder of a Palestinian and set free for lack of evidence. In the interim, it has been vaguely reported, he was involved in some kind of confrontation with law enforcement authorities in Florida, who were seeking to question him. Nonetheless, his aliya application was smoothly processed - so smoothly, indeed, that the confusing mix of authorities responsible for immigration evidently did not deem it necessary to investigate his background and assess whether, even if there was no reason to deny his application, it would be appropriate at the very least to alert the authorities here to his arrival. Indeed, they did not even take the elementary step of designating that this former murder suspect's new immigrant shipping container might merit careful scrutiny. As it turned out, the security services now allege, Teitel smuggled in an assortment of automatic weapons, sniper's rifles and pistols, along with his more mundane personal effects in that non-inspected shipment - weapons he allegedly used in a sequence of murderous hate crimes. For his part, Dimitry Kirilik reportedly immigrated from Russia in 2004 precisely to escape the consequences of his criminal activity. He was wanted by the Russian police for his involvement in a robbery the previous year. Here, too, however, suspicions and allegations against him triggered no alarms; his aliya proceeded smoothly. Even two years ago, when the Russian authorities formally submitted a request for his extradition, the Israeli authorities took no action - because, the Justice Ministry said this week, its Russian counterpart had not indicated that the request was urgent or that Kirilik was potentially dangerous. SCRUTINIZING POTENTIAL immigrants is immensely complicated. Asking would-be immigrants whether they have a criminal past - a question that is put to olim from the United States, for instance - may be straightforward enough. The logistics and legalities of ascertaining whether applicants have answered that question truthfully are far more complex. At the height of the flood of immigration from the former Soviet Union 20 years ago, moreover, instituting the kind of background checks needed to screen out undesirable immigrants was frankly unfeasible - the numbers were just too large, time was too short, and the potential for full cooperation with a collapsing USSR that had belatedly opened its exit gates was far too limited. But the flood of immigrants has long since slowed to a trickle. And the potential threat posed by dangerous arrivals, as was all-too clearly demonstrated last week, is far too great for Israel to continue the policy, or non-policy, it has maintained thus far, which amounts to little more than hoping for the best. What's needed, plainly, is immigrant profiling. Far greater coordination is plainly long overdue between the Jewish Agency, the Interior and Justice ministries, the various security agencies and all other relevant hierarchies, to ensure that Israel gives itself the best chance to safeguard its law-abiding population from new arrivals who constitute a threat. A coordinated process would also need to check backwards, to bring to light other extradition requests that may have been put aside over recent years, other red flags that may have gone unheeded, and other criminals who may be on the loose here simply because the relevant enforcement authorities don't work closely enough with each other. We may scoff at other nations for the ostensible vulnerability of their defenses against terrorism in the air, and take rightful pride in the sophistication of our protection in this limited area. But the horrific cases of Ya'acov Teitel and Dimitry Kirilik make plain that, where screening new immigrants is concerned, we are murderously negligent.