I was there! Thirty-one years ago, wedged amongst a chanting, seething sea of black-clad woman in chadors moving through downtown Tehran. So dense was the throng that even filming what we were witnessing proved almost impossible.

It was exciting, we knew the Islamic revolution – a people’s clamour for change, for spiritual renewal in the aftermath of the feeble fading of the Shah’s corrupt pro-Western regime – would change the balance of the world in which we lived, but we could not fathom how.

We knew too that we were “in on a moment of modern history”.

So impossible was it to detach ourselves from the throng that we decided as soon as we had completed whatever we could do for that day’s news transmission (thank god for the time difference with London), we would leave Tehran and head north.

Before the day was ended, as the crowds began to disperse, we crammed into our Ford transit minibus and headed for the Caspian Sea.

Why? Firstly I wanted to know how the revolution was playing beyond the metropolis, but secondly I wanted to find out what had happened to the facility that represented the West’s gravest concern.

Somewhere on the coast of the Caspian, the Americans had built an early warning “listening” station – a series of golf ball shaped domes from which they monitored Russian nuclear tests in the Urals on the other side of the sea.

I had spotted the profiles of the golf balls ten years earlier as a student.

I had driven a bus from Liverpool to New Delhi and passed this way. The problem was that I had no idea which end of the Caspian’s southern coast I had seen them, and no one would tell us.

At daybreak we started from Tabriz and headed east. We drove for much of the day, seeing little evidence of revolution beyond a few knots of khaki-clad guards in the streets.

Just as my crew was beginning to conclude that I was weak in the head and an inventor of golf ball structures – there they were! Squeezed on a hill top, white beneath the low grey cloud base.

Two teenage revolutionary guards sat on metal chairs at the gates, with guns on their laps, oblivious to what it was that they guarded.

The golf balls hummed. “Don’t go in,” I shouted. “They may have been booby-trapped. We threw stones through the open door of one of the structures.

No boom, no bang. We entered to a find a cacophony of whirring computers. Purple inked zig-zagging graphs on gridded paper spewed from the machines.

In the residential block, clothes lay on the beds, children’s toys on the floors, food on the kitchen tables. Someone had left in a hurry.

Back in Tehran, armed with fabulous film of it all, I clambered into bed and slept the sleep of the dead. I was awakened by a knock on my hotel room door. X was an intelligence officer from the British Embassy, he wanted to know what we knew and what compromises lay in our films.

I did a shameful trade. I eventually let him advise which shots concerned him in return for information as to the whereabouts of the recently delivered state-of-the art Foxbat US fighter jets.

My love-affair with Iran was in full spate, an exhilarating rollercoaster of a story that is still in full spate. No-one knows where the revolution will lead – we are no clearer today than we were in those brittle, cold February days thirty-one years ago.

I am not persuaded by reports that Iran’s Supreme Leader Ayatollah Khamenei’s presidential jet is being “made ready” to lift him out of the country in the event of an impending overthrow.

When I arrived on the tarmac at Shiraz International Airport in the south of Iran a week ago, there were no fewer than two official jetliners sitting there. An antiquated Boeing 707 and a newer Airbus.

The ruling elites in Iran (and there are many) have access to a whole range of state paraphernalia for moving about the country, and out of it. When I interviewed him on the day before Christmas Eve, President Ahmadinejad could have moved a total of some 500 officials with ease from Shiraz to anywhere within several thousand miles.

Even if I’m sceptical about the plane, I do think it is right to focus on Khamenei. His position is becoming increasingly fragile.

The death of Ayatollah Montazeri just ten days ago, served to underline how junior and unimportant an Ayatollah Khamenei was when he came to power. Montazeri was infinitely more learned and more senior. No one has ever accused Khamenei of being over endowed either with brains or spiritual insight.

He’s been a place man holding the ring between those clerics like Montazeri who did not want the clergy in government and those like the founding father of the Islamic revolution, Ayatollah Khamenei, who did.

The question remains. Who gave the order to shoot live rounds at protesters on Iran’s holiest day of Ashura? Who ordered the “assassination” of Ali Habibi, the nephew of presidential candidate Mousavi? Did Khamenei give his blessing?

The Islamic Revolution in Iran is going the way of all revolutions – it is rotting from within.

It is demonstrating its weakness by proving unable to risk arresting the actual leaders of the protests, instead jailing and killing the relatives of those leaders.

Nobel Prize winner Shirin Ebadi has already had her prize taken from her by the regime, now her sister Nooshin – a professor of medicine – has been arrested.

My sense, as the last Western journalist to look into the eyes of President Ahmadinejad, is that he is not the key to his country’s destiny. He was “favoured” by Khamenei to be regarded as the victor of the 2009 elections.

Khamenei forced him to sack a relatively liberal first Vice President Mashaei. (Mashaei was caught attending an event in Turkey three years ago at which, perish the though, women danced). I saw Mashaei in Shiraz, a surprisingly approachable man who has now been translated into Ahmadinejad’s Chief of Staff.

I found people around the president more talkative than a year ago. One man, who I had conversed with before, on the fringes of the group, confided that there were only two true loyalists left in the president’s inner circle – Mashaei and his chief press man. The rest he said “are there for the ride”.

Ahmadinejad is a religious technocrat – a town planner who’s PhD was on traffic management – a much required science in Iran.

If Khomeini falls, he falls. If Khamenei falls, the Islamic Revolution itself may unravel.

This rotting of the revolution manifests itself in the rampant corruption in the clerical and Revolutionary Guard classes. They are eating the Iranian economy from within.

Vast sectors are now in the hands of young guards who were hardly born at the time of the revolution. The volunteer Basij class – once highly ordered from above – is now at large on the streets, largely out of immediate control.

Sitting in front of Ahmadinejad at the tomb of the great Persian poet Hafeez, seven days ago, I did not feel I was anywhere near the controlling eye of the storm.

Events are running in Iran, and the revolutionary system is too divided, too much at war with itself to retrieve the initiative.

Killing may be its last recourse. In which case poor Iran must prepare for still more funerals.

Speaking of which, the government is at odds with its own Islamic law by failing to release the body of Mousavi’s nephew for burial within 24 hours of his death.

They fear the consequences of such a funeral.

I’ve been in Iran for the last couple of days.

I have been applying for a period of months for an interview with President Ahmadinejad had twice been refused and was settling down for the Christmas break, or the prospect of it, when I was contacted from Tehran and told I would have an interview yesterday.

No sooner had I landed in Tehran than President Ahmadinejad was lifting off in his presidential plane to Shiraz in the south of the country.

It gave me a chance to revisit the bureaucracy, the paranoia, the exceptional capability of so many people you meet and the parlous underperformance of what should be a brilliant state.

Officially inflation is running at 15 per cent, unofficially it’s 25 per cent. Amid all the talk of emerging economies this ought to be one and isn’t.

Everything continues to work, just. But you feel it’s down to the persistent ingenuity of the Iranians themselves and no thanks to any kind of an administration.

The revolutionary guard have seized still more of the economic drivers and thoroughly enriched themselves in the process.

The thuggish Basij stalk the streets and yet there is an overall sense of calm and businesses as usual. Even though everybody knows there is turmoil at all sorts of levels in all sorts of places – in the Grand Ayatollah Hossein Ali Montazeri’s home town of Najafabad

The opposition is disparate, but in the safety of the departure lounge people came up to me to express despair and to speak of 80 per cent of the population loathing the current setup.

To make up for our long journey to find him the presidents aides had setup a grandiose setting for our interview. The gorgeous shrine of the great 14th Century Persian poet Hafeez.

A platform was built, flowers were arranged even chocolates and stuffed dates were on hand. There’s always the fear that the stuffed dates are going to get the better of you and lead to a soft soap encounter.

You don’t see Ahmadinejad in the first flash of his arrival at the shine. A phalanx of other men obliterate his presence and then there he is in his open neck shirt and jacket and he’s sitting in front of me.

He admits to some trouble. Dismisses any question of a nuclear deadline or threats of UN sanctions and whatever the trouble has been at home he seems oblivious of the rising discontent.

But he’s probably right in claiming that nothing very dramatic is going to happen at home at least in the immediate future.

It’s an intriguing interview and at the end of it the smiles on the faces of his aides have turned something approaching discomfort if I can put it diplomatically.

Within three hours we are airborne and out and I worry how long it will be before I will ever be allowed in again.

It’s a sad place to leave and it never gets any better each time you do so.

After the interview ended the president then relayed to me his Christmas message – he speaks extensively of the ‘prophet Jesus Christ’ and of how those who believe in him should continue to do so.

He offers the prospect the son of God will return in some immaculate moment that will include his own favourite prospective returnee, the 12th Imam (sometimes described as the Hidden Imam) – it was the aura from this thought that the president referred to when he described feeling his presence in the chamber of the UN in New York.

Anyway I think we can say it was happy Christmas from him and perhaps I could humbly add from me as well, although I look forwards to engaging with you in the usual way on Xmas day. A short but sweet offering at 7.40pm

A former CIA contact of mine with specialist knowledge on the Middle East, and good connections, suggests there could be moves inside the embryonic Netanyahu government to reopen the question of bombing Iran.

Such rumours – and I will restate we are just talking about the reopening of a question – have to be taken with a pinch of salt, and it is hard to imagine that Washington will supply the ammunition Israel needs to attack Iran at this time.

The overall assessment seems to be that whatever the speculation, the Israelis cannot yet do such an attack on their own with any confidence that they would destroy the nuclear installations.

Unless, of course, they go for a nuclear option and that would appear to be beyond madness…

For their part, the Iranians say they have now installed 7,000 centrifuges in their nuclear installation at Natanz.

This is still far short of the number needed to refine the fuel necessary to make an atomic bomb.

However, it is an advance on the 5,500 centrifuges reported by the UN nuclear inspectorate earlier this year. President Ahmadinejad, fighting for re-election in June, still stresses the peaceful nuclear power ambition behind the development.

The West continues to disbelieve the “peaceful” bit.

It seems the Iranians are now actually making the centrifuges themselves having previously bought others of indifferent quality on the black market.

The Obama administration, we are told, is still desperately seeking non-nuclear diplomatic mechanisms for engaging with Iran.

We are in a pre-election maelstrom…a dangerous time…one obvious victim is the journalist Roxana Saberi (dual Iranian/ American citizenship).

She was caught working as a journalist after her permit had expired and may now be tried for espionage as early as a fortnight’s time.

Matters Iranian are pulling in all directions at once: evidently helpful on the Afghan front after the Hague meeting two weeks ago; awkward over Ms Saberi; uppity over the nuclear.