Say you live in any one of these cities: Oslo, Berlin, Paris, Madrid, Amsterdam, Edinburgh, London, Stockholm or Washington, and at 11 a.m. today the war siren goes off. You've been told it's just a drill - your city isn't being attacked by ballistic missiles or long-range rockets. Your country neither plans to attack anyone, nor is there intelligence indicating it is the target of imminent attack.

Pupils at a Jerusalem school don gas masks as part of a drill.
Photo: Ariel Jerozolimski

Slideshow: Home Front drill

Still, the wailing siren - a curiously anachronistic instrument for the 21st century - is upsetting. You do as you're told and seek out a nearby bomb shelter, or enter the reinforced-concrete room common in homes built since the 1990s.

'Post' staff goes to bomb shelter as sirens wail (amateur video by Ben Spier)

At work, there is some gallows humor as colleagues file into the bomb shelter. At school, your children will head into the shelters with their teachers. It may strike you that the authorities were imprudent in collecting for refurbishment those cardboard boxes with their plastic shoulder-straps containing gas masks and a chemical-warfare antidote.

Of course, if you do live in any of the above-mentioned capitals, this scenario is beyond far-fetched. There are no shelters. No safe rooms. No gas masks.

No one is threatening to wipe Sweden, Germany or Scotland - or any of the others - off the map. There are no Sajil II ballistic missiles aimed your way. Your country didn't absorb 5,000 rocket hits in the course of a single summer. It doesn't share a border with a country that deploys Scud D missiles. And the notion that missiles laden with WMDs could explode over your head is simply beyond imagination.

Though Muslim extremists struck in Spain, Britain and the United States, the sense that any further danger looms is not widespread. That's why no one undergoes a security check to enter a supermarket, department store or cinema. And why armed guards are not posted outside schools.

WE ISRAELIS live in a very different reality.

That truth was brought home in remarks Prime Minister Binyamin Netanyahu made at Sunday's cabinet meeting regarding Turning Point 3 - the week-long nationwide emergency drill.

The exercise is "routine," something the country does annually, he said, adding that it "reflects the special way in which we lead our lives - which, upon reflection, is not all that routine."

Want to understand the Israeli psyche? Consider that when our country was born, those with whom we sought to share this land rejected our right to exist. Though we have created a technologically advanced, Western-oriented country, and made peace with Egypt and Jordan, our "normality" still demands that a high-school graduate head not to university or for a gap year, but to basic training.

Throughout the 1950s and 1960s (when there were no settlements and no "occupation") our homeland was under attack anyway. A single example: On March 17, 1954, gunmen ambushed an Eilat-Tel Aviv commuter bus. First they murdered the driver, then they proceeded to shoot the passengers, one by one.

In the 1970s, we fought off a surprise attack on our most solemn holy day - after having withstood a war of attrition. In the 1980s, we fought bitter wars in Lebanon to fend off attacks against our northern border.

In the 1990s, we signed the Oslo Accords with the Palestinian leadership. And since then? More Israelis have been murdered by terrorists than ever before.

Efforts to reach an accommodation with a violently fragmented Palestinian polity have thus far proven fruitless. The "moderates" appear no less unyielding than the fanatics.

We caught the Syrians, to our north, building a clandestine nuclear facility under North Korean tutelage. They make no secret about hosting Hamas's politburo, pressuring it to resist even a tactical timeout in its anti-Israel belligerency.

Hizbullah dominates Lebanese affairs and provides Iran with shock-troops along our border.

Then there is Iran, which may have enriched enough uranium to manufacture a nuclear bomb by year's end. Even as Mahmoud Ahmadinejad threatens our obliteration, he insists that the Nazis did not systematically destroy European Jewry. Yet he is feted at UN forums, while Europeans shamelessly subsidize trade with his country.

That is our reality. It's the one many of us will be contemplating at 11 a.m. today, when the siren sounds.