The rise of jihadist extremism in Iraq is linked to the 2003 invasion, Jack Straw claimed today as the former Foreign Secretary put himself at odds with Tony Blair.

Mr Straw said it was 'impossible' to argue that the war ordered by Mr Blair 'played no part at all in today's events'.

Mr Blair yesterday insisted Iraq would have been 'engulfed by precisely the same convulsion' if Saddam Hussein had remained in power, as he called for new military intervention.

The ex-PM's intervention has been condemned from all sides, with London Mayor Boris Johnson claiming Mr Blair ‘surely needs professional psychiatric help’ for refusing the accept that the Iraq War was a ‘tragic mistake’.

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Former Foreign Secretary Jack Straw today insisted it was 'impossible' to claim that Tony Blair's war in Iraq played no part in today's events

Islamist jihadists are now in control of large areas of the country, plunging Iraq into its bloodiest crisis since the withdrawal of US troops in 2011. ISIS rebels, led by Abu Bakr al-Baghdadi, are said to have murdered 1,700 soldiers last week.

New pictures have emerged showing the mass execution of government soldiers by masked fanatics fighting for the Islamist State of Iraq and al-Sham (ISIS).

Mr Blair, who led Britain into the conflict alongside US President George W Bush, yesterday denied the appalling bloodshed was connected to the 2003 invasion.

‘We have to liberate ourselves from the notion that 'we' have caused this,’ the former Prime Minister wrote in an extraordinary essay. ‘We haven’t.’

FORMER COLLEAGUES, MINISTERS AND DIPLOMATS TURN ON BLAIR Former Foreign Secretary Jack Straw: 'I think it is impossible to argue that the invasion in 2003.. played no part at all in today's events.' London Mayor Boris Johnson: ‘I have come to the conclusion that Tony Blair has finally gone mad.' Foreign Secretary William Hague: 'No, I don’t think the invasion itself was a mistake. I have always thought that many mistakes occurred in the aftermath of the invasion.' Former Liberal Democrat leader Lord Ashdown said: 'I'm having a bit of a difficulty getting my mind round the idea that a problem that has been caused or made worse by killing many many Arab Muslims in the Middle East is going to be made better by killing more with western weapons.' Sir Christopher Meyer, Britain's ambassador to the US from 1997 to 2003, said: 'We are reaping what we sowed.'. Advertisement

He went on to call for decisive military response 'including military strikes against extremists in Iraq and Syria'.

In an essay on the crisis in Iraq, Mr Blair said: 'It is a bizarre reading of the cauldron that is the Middle East today, to claim that but for the removal of Saddam, we would not have a crisis.

'And it is here that if we want the right policy for the future, we have to learn properly the lessons not just of Iraq in 2003 but of the Arab uprisings from 2011 onwards.'

But Mr Straw, Foreign Secretary in Mr Blair's Cabinet from 2001-06, said it could not be denied that the 2003 invasion played a part in unrest.

He told BBC Radio 4's The World At One: 'I think it is impossible to argue that the invasion in 2003 and, in a sense still more, decisions taken in the summer of 2003, particularly for the mass de-Baathification of the Iraqi security forces, played no part at all in today's events because those were a major change in the nature and balance of power in Iraqi society.

'Would there be peace and tranquillity if there had been no invasion and Saddam had stayed in power?

'I'm pretty certain at some stage or other there would have been a major civil war in Iraq, as there has been in adjoining Syria.'

London Mayor Boris Johnson said Tony Blair has 'finally gone mad' for his call for new military intervention in Iraq

Mr Blair has come under fire from across the political spectrum for his call for new military intervention in Iraq.

London Mayor Mr Johnson declared today: ‘I have come to the conclusion that Tony Blair has finally gone mad.

‘In discussing the disaster of modern Iraq he made assertions that are so jaw-droppingly and breathtakingly at variance with reality that he surely needs professional psychiatric help.’

Writing in his Telegraph column, Mr Johnson accused Mr Blair of failing to accept the ‘truth’ that more than 100,000 dead Iraqis would be alive today if the UK and US ‘had not gone in and created the conditions for such a conflict’.

He added: ‘We utterly blitzed the power centres of Iraq with no credible plan for the next stage - and frankly, yes, I do blame Bush and Blair for their unbelievable arrogance in thinking it would work.’

Foreign Secretary William Hague insisted the 2003 invasion had been right, but mistakes were made in the aftermath

Mr Johnson – who voted in favour of the 2003 war - said that by refusing to now accept that it was 'a tragic mistake', 'Blair is now undermining the very cause he advocates: the possibility of serious and effective intervention.

'Somebody needs to get on to Tony Blair and tell him to put a sock in it, or at least to accept the reality of the disaster he helped to engender. Then he might be worth hearing,' Mr Johnson concluded.

Amid international outrage at the atrocity, US president Barack Obama is weighing up what help to give Baghdad to counter the land-grab by the al-Qaida-inspired ISIS.

The British government has ruled out any new military intervention, in part because the Commons last year voted against action in Syria.

Mr Hague told BBC Radio 4’s Today programme: ‘So many situations can arise in the world that we cannot predict that to absolutely rule all things out in all circumstances tends to be a mistake.

‘But in this situation today, in Iraq, with what we’ve seen in recent days, are we looking at a British military intervention? No, we’re not. I can’t be clearer than that.’

Britain has already offered humanitarian assistance for the Iraqi people displaced in the north, and Mr Hague hinted that British special forces could be offered.

'I’ve said that we might be able to help with counter-terrorism expertise. We are looking at that now,' he said.

However, Mr Hague, who also voted for the 2003 war, denied that the invasion had itself been a mistake.

'No, I don’t think the invasion itself was a mistake. I have always thought that many mistakes occurred in the aftermath of the invasion.

‘It’s entirely possible to say that it was the right thing to remove Saddam Hussein, but that mistakes were made in the aftermath of that.’

Critics of Mr Blair have lined up to condemn his intervention.

Former foreign minister Lord Malloch Brown urged Mr Blair to 'stay quiet' because his presence in the debate was driving people to oppose what might be the necessary response.;

Clare Short, who quit Mr Blair's cabinet in the aftermath of the 2003 invasion, said he had been 'absolutely, consistently wrong, wrong, wrong' on the issue, and opposed more strikes.

Ukip leader Nigel Farage dismissed Mr Blair as an 'embarrassment' who should hold his tongue - and demanded 'an end to the era of military intervention abroad'.

U.S. President George W. Bush and British Prime Minister Tony Blair shake hands in 2003, after discussing the war with Iraq

Sectarian violence is tearing Iraq apart and Mr Blair says the West should intervene to ensure that Islamist fanatics are 'countered hard, with force'

Scotland's First Minister Alex Salmond added his voice to the chorus, accusing Mr Blair of 'breathtaking amnesia' over his reasons for invading Iraq.

And Sir Christopher Meyer, Britain's ambassador to the US from 1997 to 2003, said the handling of the campaign against Saddam was 'perhaps the most significant reason' for today's violence.

'We are reaping what we sowed,' he said.

Former Liberal Democrat leader Lord Ashdown said: 'I'm having a bit of a difficulty getting my mind round the idea that a problem that has been caused or made worse by killing many many Arab Muslims in the Middle East is going to be made better by killing more with western weapons.'

Blair's bizarre claims - and the reality: One of Britain's most distinguished generals says former Prime Minister is in 'complete denial' over Iraq

General Sir Michael Rose is a retired British Army general, as well as commanding 22 SAS, he was also appointed Commander of UNPROFOR Bosnia in 1994 during the Yugoslav Wars

Anyone who doubts Tony Blair's self-delusion over Iraq should look at the 2,800-word essay he has posted on his website in defence of his decision to go to war.

He remains in complete denial over the disaster he inflicted not only on the people of Iraq, but also on many millions throughout the Middle East as a result of the 2003 invasion.

It goes without saying that if you start a war, you should be sure that the end result will be demonstrably better than the situation prior to the conflict.

Only someone who has lost touch with reality could possibly claim Iraq today is more stable or that life has become better for its inhabitants.

Blair accepts not a shred of responsibility and still refuses to apologise for taking us to war. So let us examine what he says point by point – and show his false logic for what it is.

CHEMICAL WEAPONS

CLAIM: One of the most extraordinary arguments by Tony Blair in his essay is that, because Syria's President Assad has used chemical weapons, this retrospectively justifies invading Iraq, where no such weapons were found.

'Is it likely that, knowing what we now know about Assad, Saddam, who had used chemical weapons against both the Iranians and his own people, would have refrained from returning to his old ways?' he asks.

TRUTH: Leave aside, as too preposterous to merit a response, the argument that because one dictator in one country has used chemical weapons, it follows that another in a completely different country would have done so too.

It was already quite clear by 2003 that Iraq did not possess weapons of mass destruction and that Saddam Hussein was no threat to anyone.

For, following the Iraq/Iran war and Saddam's disastrous invasion of Kuwait in 1990, Iraq was being adequately contained militarily by the West.

It was not only subject to punitive economic sanctions and UN arms inspections, but was being bombed almost daily by the US Air Force in Operation Desert Fox. Although Saddam Hussein may have retained a latent ambition to obtain weapons of mass destruction, neither the UN inspectors before the war or the Iraq Survey Group afterwards have ever found any trace of such weapons.

WE'D BEATEN AL QAEDA

CLAIM: Blair says the West had overcome the terrorist threat in Iraq before withdrawing. 'Three or four years ago, al Qaeda in Iraq was a beaten force,' he writes.

TRUTH: To say al Qaeda was ever 'defeated' in Iraq is nonsense. True, significant damage was done to its infrastructure while US and British troops were still in the country, but it was never defeated.

Like all insurgents, the terrorist group merely laid low until the enemy became weak or distracted. But the key point is that neither al Qaeda nor any other extreme jihadist group had any presence in

Iraq before the 2003 invasion. Saddam Hussein was far too brutal to allow that.

After the invasion, insurgents piled into the country. They were encouraged by disenchanted loyalists from Saddam's Ba'athist party – all Sunni Muslims – who were furious at the toppling of their leader and the rise to power of rival Shia Muslims under Western auspices.

The Sunnis had, after all, ruled in Iraq since 1638, when the Sunni Turkish Ottomans took over Baghdad from the Persians.

Saddam Hussein, pictured here during his trial in 2006 in Baghdad, was no threat to any country by 2003, according to General Sir Michael Rose

THE ARAB SPRING

CLAIM: If Iraq hadn't been invaded in 2003, says Blair, Saddam Hussein's regime would not have survived anyway – 'it would have been engulfed by the 2011 Arab Spring uprisings that swept Tunisia, Libya, Egypt, Yemen, Bahrain and Syria.

TRUTH: The invasion of Iraq and its terrible aftermath was the cause of the Arab Spring. This is because the young people involved in the uprisings throughout the Middle East felt empowered by the removal of Saddam, who had ruled with an iron fist for 24 years.

Many were appalled by what they regarded in Iraq as Western interference in Arab affairs, which encouraged them to overthrow their pro-Western dictators.

It was no surprise subsequently that what started out as a series of anti-West pro-democracy revolutions would soon be hijacked by Islamic extremists.

BLAME IRAQ'S PM

CLAIM: Rather than accept responsibility himself, Blair says the current Iraqi regime is to blame for the chaos: 'The sectarianism of the Maliki government snuffed out what was a genuine opportunity to build a cohesive Iraq'.

TRUTH: To blame Prime Minister Maliki takes some beating for sheer gall. Maliki may be corrupt, partisan, authoritarian and a puppet of Iran's Shia Muslim regime.

But Blair brazenly seems to dismiss the fact that he would never have been in power had the 2003 invasion not taken place. General Colin Powell, US Secretary of State for Defence at the time of the invasion, famously remarked: 'You break it, you own it'. Blair broke Iraq but simply won't accept any responsibility for doing so.

IT'S OBAMA'S FAULT TOO

CLAIM: Blair suggests that President Barack Obama should have kept his soldiers in Iraq: 'There will be a debate about whether the withdrawal of US troops happened too soon'.

TRUTH: US troops had been in Iraq for nearly nine years – from March 2003 to December 2011 – numbering 170,000 in 500 bases at their peak. The war had by then cost the US government some $800billion and 4,500 Americans had been killed.

Does Blair think America should have kept up this loss of blood and treasure indefinitely? In addition, the US had spent a staggering $30billion on training and equipping the Iraq army.

What they could never do, however long they stayed, was to give them the will to fight.

MILITARY STRIKES

CLAIM: We need a decisive military response, says Blair, 'including military strikes against extremists in Iraq and Syria'.

TRUTH: As we have seen, military intervention invariably makes things worse. So far, our adventures in the Middle East have served only to increase hatred of the West and recruit still more insurgents to fight alongside our enemy.