A documentary being broadcast on Al Jazeera on Tuesday night will set out what many dispassionate experts on the 1988 Lockerbie bombing have always believed to be the true account of the worst terrorist attack ever carried out on British territory and the worst terror attack on American civilians with the exception of 9/11.

The film, “Lockerbie: What Really Happened,” blames Iran for the bombing of Pan Am Flight 103 over Lockerbie, Scotland, in December 1988, with the loss of all 259 passengers and crew and 11 people on the ground. It makes plain that Tehran was avenging the accidental downing by the USS Vincennes of one of its civilian airliners, Iran Air Flight 655, in the Persian Gulf six months earlier, with the loss of all 290 people on board.

And it shows that the bombing was carried out on Iran’s behalf by Ahmad Jibril’s Syrian-based Popular Front for the Liberation of Palestine-General Command, a terror group well experienced in the dark arts of smuggling barometric pressure devices onto airplanes to blow them up at pre-planned altitudes well into their journeys. Had Flight 103 not been delayed in taking off for New York from London’s Heathrow Airport, the explosion that tore it apart would have done so over the Atlantic Ocean, and none of the wreckage subsequently pieced together by investigators would have been retrieved.

The terrible, abiding failure at the heart of the Lockerbie affair is that despite all that painstakingly collected evidence, which pointed unerringly to a Frankfurt-based PFLP-GC cell — several of whose members were arrested at the time — as the perpetrators of the terrorist outrage, the investigation’s initial focus on Iran, Syria and Jibril later skewed improbably toward Libya. Some theorists suggest this was because of the West’s desire to avoid antagonizing Hafez Assad’s Syria, whose support it needed against Saddam Hussein’s Iraq.

Abdelbaset al-Megrahi, who was found guilty of the 1988 Lockerbie bombing and sentenced to life imprisonment, is greeted by Libyan leader Muammar Gaddafi, in Tripoli, Libya on Friday, Aug. 21, 2009 following his release on compassionate grounds because he had terminal cancer. He died in May 2012 (photo credit: AP Photo/Jamahiriya Broadcasting via APTN)

Abdelbaset al-Megrahi, who was found guilty of the 1988 Lockerbie bombing and sentenced to life imprisonment, is greeted by Libyan leader Muammar Gaddafi, in Tripoli, Libya, on Friday, Aug. 21, 2009, following his release on compassionate grounds because he had terminal cancer. He died in May 2012 (photo credit: AP Photo/Jamahiriya Broadcasting via APTN)

The only man ever convicted for involvement in the bombing was a Libyan intelligence officer, Abdelbaset al-Megrahi, who was found by three Scottish judges to have placed a suitcase containing the bomb on a flight from Malta to Frankfurt, from where it was ostensibly transferred to a flight to London’s Heathrow, before detonating on Flight 103 a little more than half an hour after the Pan Am plane took off for New York. Megrahi, who was jailed in 2001 after a trial in which his fellow alleged Libyan conspirator, Lamin Fhima, was acquitted, went to his death in 2012 insisting on his innocence.

Year after year, ever larger leaps of faith have been required to sustain the credibility of Megrahi’s conviction. The process by which he was identified has been severely undermined. Bomb fragments that supposedly could only have originated in Libya later turned out to have been misidentified. In 2007, a thorough Scottish Criminal Cases Review Commission found a series of grounds to justify concerns that a miscarriage of justice had occurred.

Hasan Rouhani, center, poses before a large portrait of the late Iranian revolutionary founder Ayatollah Khomeini, the day after being elected to Iran's presidency, on June 15, 2013 (Photo credit: AP/Ebrahim Noroozi)

Hassan Rouhani, center, poses before a large portrait of the late Iranian revolutionary founder Ayatollah Khomeini, the day after being elected to Iran’s presidency, on June 15, 2013 (Photo credit: AP/Ebrahim Noroozi)

What’s new about the Al Jazeera documentary is the testimony of a former Iranian intelligence officer, Abolghasem Mesbahi, who defected to Germany in the 1990s. Mesbahi details the chain of responsibility for the Lockerbie bombing — executed by the Frankfurt-based cell headed by Jibril’s colleague Hafez Dalkamoni — all the way up to the highest echelons of the Iranian leadership.

Abolghasem Mesbahi (photo credit: YouTube screenshot)

Abolghasem Mesbahi (photo credit: YouTube screenshot)

Mesbahi, who once reported directly to former Iranian president Akbar Hashemi Rafsanjani, asserts that “Iran decided to retaliate [for the downing of its own Flight 655] as soon as possible. The decision was made by the whole system in Iran and confirmed by Ayatollah Khomeini.”

The aftermath of the 1994 AMIA bombing in Buenos Aires (photo credit: Newspaper La Nación (Argentina)/Wikipedia Commons)

The aftermath of the 1994 AMIA bombing in Buenos Aires (photo credit: Newspaper La Nación (Argentina)/Wikipedia Commons)

What is well worth recalling is that the same Iranian defector, Abolghasem Mesbahi, provided vital information to Argentinian investigators who were probing the 1994 terrorist attack on the AMIA Buenos Aires Jewish community center building, in which 85 people were killed. So compelling was Mesbahi’s evidence, indeed, that the indefatigable Argentinian investigator Alberto Nisman was able to trace responsibility for that terrorist attack directly to a meeting of Iran’s National Security Council held on August 14, 1993, and to compile sufficiently persuasive proof of Iran’s responsibility for the crime as to have several leading Iranian figures, including former defense minister and Revolutionary Guards commander Ahmad Vahidi, and last year’s failed Iranian presidential candidate Mohsen Rezai, placed on an Interpol “red notice” list.

PFLP-GC chief Ahmed Jibril (right) pictured with Hezbollah leader Hassan Nasrallah in Beirut in May 2002. (photo credit: AP Photo/Bassem Tellawi)

PFLP-GC chief Ahmed Jibril (right) pictured with Hezbollah leader Hassan Nasrallah in Beirut in May 2002. (photo credit: AP Photo/Bassem Tellawi)

Nisman headed an underfunded and controversial investigation in an Argentina whose president at the time of the AMIA bombing, Carlos Menem, had been personally terrified at the consequences of pointing the finger of blame at Iran. If Nisman proved capable of assembling the evidence necessary to credibly demonstrate Iran’s responsibility for that blast, it should not now be beyond the capabilities of British and American investigators to reopen and reconsider the Lockerbie case, in order to examine the culpability of Iran and of Jibril’s PFLP-GC.

It is quite the coincidence that this latest information on Iran’s responsibility for Lockerbie has emerged in the very week that Israel’s Prime Minister Benjamin Netanyahu, speaking at a press conference surrounded by weaponry intercepted on the high seas en route from Iran to terror groups in Gaza, castigated the international community for failing to internalize and act against Iran’s relentless orchestration of terrorism.

Prime Minister Benjamin Netanyahu speaks in Eilat on March 10, with the Iranian missile shipment behind him (photo credit: AFP/Jack Guez)

Prime Minister Benjamin Netanyahu speaks in Eilat on March 10, with the Iranian missile shipment behind him (photo credit: AFP/Jack Guez)

It is even more of a bitter coincidence that Mesbahi’s information is being broadcast even as a search is on for a Malaysian Airliner that vanished over the open seas with the presumed loss of all 239 people on board. Whatever proves to have caused the disappearance of that plane, the fact is that the Lockerbie bombers sought an identical result — the loss of Pan Am flight 103 over the ocean, which they hoped would prevent any possibility of proving their guilt.

But Flight 103 took off late, and was blown up over land — over the sleepy and hitherto anonymous Scottish town of Lockerbie. The evidence to show who had ruthlessly condemned to death its 259 passengers and crew, and those 11 more people on the ground, lay scattered but retrievable, and was indeed retrieved. A quarter of a century later, it should not be too much to expect that American and British investigators will galvanize themselves to look again at that evidence, and if they can trace it to Tehran, belatedly bring the perpetrators to justice.

A member of the public looks at the main memorial stone in memory of the victims of Pan Am flight 103 bombing, in the garden of remembrance at Dryfesdale Cemetery, near Lockerbie, Scotland. Saturday Dec. 21, 2013. Pan Am flight 103 was blown apart above the Scottish border town of Lockerbie on Dec. 21, 1988. All 269 passengers and crew on the flight and 11 people on the ground were killed in the bombing. (photo credit: AP Photo/Scott Heppell).

A member of the public looks at the main memorial stone in memory of the victims of Pan Am flight 103 bombing, in the garden of remembrance at Dryfesdale Cemetery, near Lockerbie, Scotland. Saturday Dec. 21, 2013. Pan Am flight 103 was blown apart above the Scottish border town of Lockerbie on Dec. 21, 1988. All 269 passengers and crew on the flight and 11 people on the ground were killed in the bombing. (photo credit: AP Photo/Scott Heppell).