Osama and Saddam, are they laughing at us?
Resistance in Iraq is growing more deadly by the day.
It is becoming more co-ordinated, more sophisticated and it is beginning to bear the hallmarks of serious organisation. It is no longer just 'dead-enders', as the Pentagon is fond of calling the old regime.
The spectre of a guerrilla fightback by Islamic militants, inspired by al-Qaeda's rhetoric has become a murderous reality as Western troops who saw themselves as 'liberators' are increasingly viewed as occupiers and 'infidels' in a Muslim land.
So who exactly is involved in the remorseless pattern of bloodshed and death and what are their motives and aims? Intelligence analysts believe there are three groups and there are worrying signs that they are beginning to work together.
'Seasoned international terrorists'
The first is made up of former middle-ranking members of Saddam Hussein's elite militias and security forces. They have military expertise and access to vast hidden arsenals, including many thousands of rocket-propelled and surface-to-air missiles. They have financial resources too - money looted from the banks by Saddam and his sons for this very purpose on the eve of war.
This group can mobilise resistance cells to strike with deadly effect at US convoys and checkpoints using improvised explosive devices.
However, it is the other two groups - comprised of Islamic militants - who arguably pose the greatest long-term threat. Their aim is to reduce this oil-rich and strategically important country to ungovernable chaos and so destabilise the whole region.
The first of these two groups known to be active in Iraq is made up of seasoned international terrorists, some of them refugees from the war in Afghanistan in 2001.
Hardened Arab fighters joined forces with Ansar al Islam (the Partisans of God), an extremist group which ran a Taleban-like enclave in northern Iraq until they were attacked by US forces earlier this year.
This group is around 200 strong and has expertise in car bombings, assassination and the use of crude poisons. Two of Ansar's leaders have recently been arrested in the northern city of Mosul and a top US commander has admitted that 'Ansar al Islam is our principle organised terrorist adversary in Iraq right now.'
Co-operation and co-ordination
The second, more loosely structured, group of Islamic activists is made up of young foreign fighters fired with anger against 'the infidel'. They are making their way from Syria, north Africa and the Gulf to fight a holy war in the same way their predecessors in the Eighties flocked to Afghanistan to fight the Soviets and again in 2001 to join Bin Laden and the Taleban.
There are real fears that young Muslims from Britain will be drawn in. Bin Laden is an arch-propagandist and all too aware of the powerful image of the jihad first conjured up in the dust and blood of battle in Afghanistan.
It is hard not to hear the echo of laughter from the lips of both Saddam Hussein and Osama Bin Laden
Because of the ferocity and efficiency of the recent bombings, US and British sources now believe there is contact between the three groups and, increasingly, some degree of co-ordination.
The nightmare for everyone in Baghdad is the random bomb on the street. Arriving at our hotel, the Panorama team found it sealed off behind a makeshift barrier manned by nervous Iraqi guards.
Our car radio announced a bomb had exploded at the Baghdad Hotel, just up the road. In an attempt to kill Americans staying there, a bomber had blown up the security post, killing himself and all six Iraqi guards.
Resistance: a blaze near a Baghdad hotel
Fear of suicide bombers now rules Baghdad's streets. The targets are Westerners, but the causalities are overwhelmingly innocent Iraqis. An estimated 2,000 of them have lost their lives since the official end of hostilities in May.
Few Iraqis you talk to want Saddam Hussein back, but equally they want troops to go now and leave them to run their own affairs. But they know Islamic militants are hoping to perpetuate the 'failed state syndrome' which Bin Laden exploited with success in Afghanistan.
The longer terror stalks the benighted country, the longer those two men - one with impenetrable mountains on the Afghan border, the other in a barren desert place - will gloat. It is hard not to hear the echo of laughter from the lips of both Saddam Hussein and Osama Bin Laden.