IS THIS PART OF ISIS PLOT TO BRING FEAR TO EUROPE?

ALREAdY, competing theories are raging about why the Airbus 320 plunged into the Mediterranean. Of course, it could have been mechanical failure, though the plane has an excellent safety record.

Or the aircraft could have been brought down deliberately — either by a bomb, by terrorists who somehow managed to enter the cockpit — like 9/11 — or one of the flight crew.

That latter theory would not be without precedent. In 1999, Gameel AlBatouti, an Egyptian pilot for EgyptAir and a former officer for the Egyptian Air Force, deliberately killed all 217 aboard EgyptAir Flight 990 shortly after it took off from New York by nosediving it into the ocean — as he repeated Islamic religious expressions.

What we can categorically conclude at this juncture is that nothing said by any of the officials who make up the atrociously corrupt Egyptian regime, led by the ruthless and blood-drenched dictator Abdel Fattah el-Sisi, can be taken at face value.

Indeed, the response thus far reveals shocking parallels with the lies and obfuscations that Cairo’s political elite spewed out after a Russian Metrojet flight was brought down over Sinai last year, killing all 224 on board.

It subsequently transpired that, within days, both the Russian and Egyptian authorities were sure a bomb had brought down the holiday airliner.

however, in a desperate effort to protect its crucial but already devastated tourism industry, the Egyptian regime bluffed and lied for months in the hope of limiting the economic fallout — despite the astonishing fact that, within weeks, they had arrested the airport employee at Sharm el-Sheikh airport who was suspected of having planted the bomb.

Most strikingly, the Russians were quick to highlight a terrorist attack as the most likely cause.

And within hours of yesterday’s incident, the head of Russia’s Federal Security Service boldly stated that the plane’s disappearance was ‘ in all likelihood’ the result of ‘ a terrorist act’, while Egyptian officials spouted an endless series of selfcontradictory statements.

Certainly, the recent itinerary of yesterday’s downed EgyptAir plane does not inspire much confidence in the theory that this was just an unfortunate accident.

It had, for example, recently stopped at the provincial Egyptian cities of Luxor and Alexandria, most likely to pick up passengers and freight.

What is particularly chilling is that just two months ago, an EgyptAir flight from Alexandria to Cairo was hijacked by a deranged Egyptian with a fake bomb strapped to his body.

ThE fact he could smuggle what looked like a suicide vest onto the plane surely tells us all we need to know about security at Alexandria. Sharm el-Sheikh airport is still being boycotted by most international airlines because of its breathtakingly lax security measures. But rules and regulations at the country’s other airports are also undermined by an entrenched culture of bribery, laziness and nepotism.

Cairo’s main international airport, for instance, is such a shambles that, according to one former head of security, a donkey was recently allowed to roam around its interior for weeks.

The other possibility if the plane was downed — one that would have greater repercussions for British travellers — is that a bomb could have been smuggled on board in Brussels or Paris, the plane’s final two stopovers before it took off for Cairo.

Yesterday, French President Francois hollande announced that all airport employees who potentially had access to the plane would be the prime focus of the initial investigation. he made that decision with good reason.

Astonishingly, 70 workers at Paris airports suspected of being radical Islamists recently had their passes revoked.

Elsewhere in Europe, Berlin airport knowingly employed a man with Islamist links for ten months; and at least two of the Brussels bombers appear to have worked as cleaners at the city’s airport for some five years.

Anti-terrorism experts have long highlighted how easy it might be for an organised group to smuggle a bomb onto a plane. Airport vehicles, for instance, are subject only to cursory searches, so could be used to plant a concealed package underneath the plane, or in the cargo hold.

Equally, corrupt employees could help each other out by moving packages around the airport undetected. That is the favoured way of doing things among drug smugglers.

But it takes on a completely new dimension if you have a network of dedicated Islamists who are working in tandem to carry out a specific terror plot at a particular airport.

Although ISIS have yet to claim responsibility for yesterday’s tragedy, its supporters worldwide are predictably jubilant.

For they understand that, even if it turns out to have been an accident, the crash could signal the death knell for Egypt’s tourism industry. Recent polls reveal the main reason young Arabs join Islamic State is a chronic lack of employment opportunities at home — so yet more economic misery in Egypt will be a boon for the tireless Islamist recruiters.

Meanwhile, the murdered dictator President Gaddafi’s anti-aircraft missiles in Libya have fallen into jihadists’ hands — putting aircraft flying over that country in danger.

CREdIBLE terrorism experts are warning that ISIS in Libya may use speedboats to attack cruise ships and small merchant vessels in the Mediterranean. It would not be an exaggeration to say we face the imminent outbreak of a relentless ISIS- led campaign of murderous terrorism.

With each passing month, it seems ever clearer — after the attacks in Paris (twice), Sinai and Brussels — that Islamic State has a plan to terrorise us on land, sea and in the air — a ferocious campaign that would be unprecedented in modern history.

The question now is whether our too- often self- serving and passive political leaders have the wherewithal to combat this mortal threat.

John R. Bradley is the author of four books on the Middle East.