The close scrutiny of the young tourists shows the SIS harbours deep suspicions when it comes to Israeli activity.
On Rupert Murdoch's Sky TV the movie Munich can be guaranteed to pull in the viewers when it is recycled every few months or so.
It tells the story of the operation in which former Israeli Prime Minister Golda Meir ordered Mossad to kill all those involved in Black September's assassination of Israeli athletes at the Munich Olympics.
It is an apt reminder of the "eye for an eye" form of Israeli justice for which the Middle Eastern democracy is renowned.
New Zealand's own well-publicised skirmish with Israel is completely anodyne by comparison.
Israel had to tender a formal apology after two of its "agents" were jailed here in 2004. The pair were caught red-handed trying to steal New Zealand passports.
They were ultimately whisked out of New Zealand before their sentences were fully served. But it is now obvious that our own spooks still harbour deep suspicions when it comes to Israeli activity in foreign countries, including our own.
The big question that remains unanswered is what provoked the Security Intelligence Service to seek John Key's permission to investigate the swift departure of three Israeli backpackers from New Zealand after their friend and colleague was killed in the February 22 lunchtime earthquake.
Surely the SIS's suspicions were not raised simply because the three young tourists left New Zealand on the afternoon of February 23 (not within 12 hours as reported in the Southland Times' original story).
Surely, it won't have escaped notice that many other foreign nationals - including United States Assistant Secretary of State Kurt Campbell and former US Deputy Secretary of State Richard Armitage, who were in Christchurch for the United States-New Zealand partnership forum - also got out of town very quickly indeed.
They were taken by air force Hercules to Wellington on the evening of February 22 and - with many others at the forum - were given temporary travel documents so they could leave New Zealand.
In fact, the New Zealand Government made arrangements so that many foreign nationals - including the three Israelis - could fly out of Christchurch on RNZAF aircraft back to Wellington.
Israel was just one of about 20 countries to send diplomatic personnel to Christchurch to get their people out.
As one of those in Christchurch during the earthquake, I can attest to the obvious human desire to "get the hell out of there" which anyone who had nowhere left to stay must have felt.
So, why the inordinate Government focus on Israel and its citizens?
According to news reports, Key said the security intelligence officials in his office "were instantly suspicious of the Israelis when they realised they had fled".
He signed warrants so the SIS could make further investigations. Investigations by multiple agencies also probed an unauthorised Israeli search and rescue mission that was found in the Christchurch red zone and whether the security of the police national computer system had been breached.
The dead Israeli's cellphone and laptop, found in the white van in which he was crushed to death - were also investigated.
But no evidence was found to link the four Israelis with security breaches or the Israeli spy agency.
Key has naturally come in for some criticism over the way he fronted - or more accurately didn't front - the "Mossad" story when questioned by the travelling press corps.
His initial comment - that it "wasn't in the national interest" - simply fuelled further news stories.
What Key has yet to explain is why he thought it necessary to seek personal assurances from Israeli Prime Minister Benjamin Netanyahu that the four young Israelis were simply innocent backpackers.
That sort of assurance is not normally put to a foreign leader - especially in a quake aftermath.
Israeli Ambassador Shemi Tzur is sticking to his own foreign ministry's official script. But inquiries suggest Tzur did quickly send his consul to Christchurch after the quake struck.
The consul flew to Dunedin and drove up to Christchurch on February 22 where he made arrangements for the three young Israelis to get on an air force 757 out of Christchurch the next morning.
The trio were interviewed by police - then left Auckland later that day to fly back to Israel.
What this whole affair suggests is that the New Zealand Government is keeping very close tabs indeed on Israeli activities here - official and otherwise.
That may be the real story.