Simon Crean’s ill-fated term as federal Labor leader is barely remembered these days. In a brief, grey interlude between Kim Beazley and Mark Latham, the former ACTU leader struggled against an ascendant John Howard and constant destabilisation within his own party.

But a decade on, Crean’s short tenure looks increasingly like a lost opportunity for Labor. Crean was an unpopular opposition leader who languished in the polls. But he took a number of brave stands on matters of substance.

Crean was an early proponent of reforming the ALP party structure to reduce the power of trade unions and factional bosses.

But it was in foreign policy where Crean will be remembered, for his principled opposition to the invasion of Iraq.

By insisting that Australia should not intervene in a foreign war of aggression without a United Nations mandate, Crean ensured that the invasion of Iraq was not waved through with bipartisan support.

It ensures that the war, justified on the lie of weapons of mass destruction, and committed to despite the opposition of millions of ordinary Australians, will forever be a stain on the Liberal-National government of John Howard.

Needless to say, Tony Abbott was a member of the government that led Australia to war against Iraq: a cabinet minister at the time of the invasion, and also the Coalition’s Leader of the House of Representatives.

Eleven years later, it’s worth returning to the speech Crean gave to Parliament in February 2003, as the drums of war beat ever louder.

Pointing out that the ANZUS treaty did not oblige Australia to intervene in support of the US, Crean carefully picked apart the threadbare logic of the ‘Coalition of the Willing’.

“No link has yet been made between Iraq and al-Qaeda,” he said. “The weapons inspectors have not been given the chance to complete their job. It has not been authorised by the United Nations.”

John Howard had a plan for war, he argued, but no plan for peace. He had committed Australian troops to an illegitimate war, “not yet declared … without the mandate of the Australian people, the Australian parliament or the United Nations.”

All of it was true. War never was declared. A link between Saddam Hussein and Al Qaeda never was established. No weapons of mass destruction were ever found.

None of it mattered. John Howard took Australia to war. The rest, as they say, is history.

And what a bloody, brutal, inglorious history it has been. As we know, the US occupation of Iraq began in a blinding aerial bombardment and the blitzkrieg of Saddam Hussein’s demoralised army.

But, just as Crean and many others had warned, the US had no plan for peace. When a devastating insurgency exploded in 2004, the US was sucked into a street-by-street civil war in a disintegrating Iraqi society.

By the time President Barack Obama pulled US forces out in December 2011, nearly 5,000 Coalition soldiers had been killed. Estimates of the Iraqi death toll range from 69,000 to an astonishing half a million.

Hundreds of thousands more have been seriously injured.

Australia must bear some responsibility for these deaths. We were one of only four nations to actively contribute troops to the invasion.

This is the dispiriting history with which we now confront the latest round of calls for intervention in Iraq, in the wake of the dramatic events over the last week, in which the insurgent group ISIS (an English-language abbreviation for the Islamic State of Iraq and al-Shams; perhaps a better acronym is the Arabic “DAASH”) have taken over Iraq’s second-largest city of Mosul.

The disaster in Mosul came as a complete surprise to most in the West, who have stopped paying attention to the increasingly beleaguered administration of Nouri al-Maliki since the US withdrawal in 2011.

The capture of Iraq’s central bank, along with half a billion dollars and plenty of Iraqi Army weaponry, caused everyone to sit up and take notice.

ISIS is a splinter group of the Syrian insurgency: just another runaway spot fire in a broader Mesopotamian conflagration.

Originally aligned with the notorious Al Qaeda in Iraq and commanded by Abu Musab al-Zarqawi, ISIS was sucked into the Syrian civil war after the implosion of Bashar al-Assad’s rule.

With the rump of the Syrian government now focused on saving its Alawite heartland around Damascus and the Syrian coast, vast swathes of Syria descended into insurgent badlands, fought over by increasingly brutal jihadist groups.

As the momentous conquest of Mosul makes clear, the eventual victor of that Darwinian struggle was ISIS, which has now carved out a fluid territory encompassing eastern Syria and western Iraq.

As a result, the Syrian civil war has effectively spread to Iraq, spreading horrifying violence in its wake, and mortally threatening the corrupt and illegitimate government of Nouri al-Maliki.

The violence currently underway in Syria thus seems certain to move to Iraq, sucking in foreign fighters from as far afield as Chechnya and Saudi Arabia, and further destabilising an already volatile region.

For those who warned of the unpredictable consequences of toppling Saddam Hussein back in 2003, there can be little to gloat about.

“We haven’t yet come to terms with just how much damage the invasion of Iraq has done,” Waleed Aly pointed out last week. “It’s likely we won’t fully know for decades.”

That hasn’t stopped the true believers from repeating their calls for further intervention, as though further violence can come somehow dampen the inferno.

The most craven was former British prime minister Tony Blair’s recent essay on his website, in which he blamed the current situation on the failure of the West to intervene in Syria. [insert link: http://www.tonyblairoffice.org/news/entry/iraq-syria-and-the-middle-east-an-essay-by-tony-blair/ ]It’s a view described by Blair’s critics in Britain as “unhinged” and “bizarre.”

But it’s also a view shared by some hardliners in Australia. Certainly, Tony Abbott appears to harbour little guilt for the role Australia played in Iraq.

Indeed, he’s only too ready to beat the drums of war, telling President Obama that Australia stood ready to support the US should it go back into Iraq.

Yesterday, Abbott warned in Parliament that the Iraqi situation “is a security disaster for the Middle East and for the wider world”.

“No-one should underestimate the difficulty that this development poses to the people of Iraq, to the people of the Middle East and ultimately to the people of the whole world,” the Prime Minister said.

The irony should not be lost on anyone, because it was the administrations of George W. Bush, Tony Blair and John Howard back in 2002 and 2003 who “underestimated” the difficulties in Iraq. And yet here we are in 2014, with a Coalition Prime Minister once again warning of the dangers of terrorists in foreign lands.

Thankfully, at this stage, Australia does not appear to be contemplating another Iraq intervention. Defence Minister David Johnston has stated that the government is not contemplating putting boots on the ground.

The muscular delusions of liberal interventionists die hard. There is always a temptation, it seems, even amongst ordinarily progressive politcians, to commit military force to solve problems that should be the province of patience, diplomacy and aid.

But what, in the end, does terrible violence in Iraq and Syria have to do with Australia? On any sane reading of Australia’s national interest, almost nothing.

Australia should never have invaded Iraq in the first place, and neither the Coalition, Labor nor the foreign policy establishment has ever mounted a convincing argument in favour of Australian intervention in the unstable politics of the Middle East.

Only the truly deluded can still believe they can put Humpy Dumpty back together – again.