A decade has passed and the world is in chaos. For all our sakes, can we all move on from 2003, please?

If recent events in Ukraine were not disturbing enough for those who might occasionally worry about the future for their children and grandchildren, one need only now look towards the Middle East, and a little further.

The aftermath of the Arab Spring. Egypt. Syria. An isolated Israel that seems to have lost all hope of establishing a meaningful alliance against a soon-to-be-nuclear Iran, and has now ended up forming stranger ones. A pernicious and persistent strain of Islamism remaining in Afghanistan, parts of Pakistan and Nigeria, to name but a few.

And finally, the coup de grâce: the overspill of ISIS Islamists from Syria into large parts of Iraq, threatening, in a symbolic poke in the eye for the West, to realise a long-held goal. A fanatical and oppressive religious autocracy; a Caliphate.

It is difficult to recall a moment since the 1960s when the world has been in such an unstable geopolitical position. The bipolar certainties of the Cold War are now replaced with the unpredictability of a multi-polar world. And all the while, we have Western countries and their governments seemingly stuck as powerless onlookers, rabbits caught in the headlights of their own recent history in Afghanistan and Iraq.

And nowhere is this more the case than the British Labour party. We cannot look at the current situation in Iraq without reflexively referring back to 2003. For those who disagreed with it, it is a perfect chance to say, ah well, that’s because of what we did. Never again. We still cannot forgive and forget, eleven years after the invasion and seven since its chief architect left office. We cannot help but re-fight old battles.

Trouble is, it may make us feel better, but it doesn’t really help, does it? While modern Iraq provides a new set of challenges, we are still, it seems, fighting that internal battle. We are seemingly close to the position that we should never intervene in any conflict, ever again, because of what happened. It might of course have escaped our notice, of course, that the ISIS invasion might not be coincidence for different reasons: that an intelligent ISIS general might just be thinking, “of course! Let’s take the war to Iraq: they’ll never follow us there after last time”.

And yes, looking at Syria, it is difficult to escape the conclusion that Labour foreign policy seems to have morphed, too often, into whatever-Tony-Blair-did-let’s-do-the-exact-opposite. In a similar way to how Obama’s foreign policy has so often been whatever-George-Bush-did-let’s-do-the-exact-opposite. We can now see how well that has worked out with Russia. And Iran.

But the important debate is not about whether we agree with Tony Blair’s latest intervention. We can agree or disagree, and he is hardly in a position to dictate Labour policy any more anyway. Does it really matter?

No, the real issue is whether we can get unstuck; whether we allow ourselves the headspace to think about the world situation we find ourselves in now.

That situation is one which may one day, a long way off though it might seem now, require concerted military action on the part of the West – and potentially less savoury allies, should they prove necessary – to defeat probably the most serious threat to our way of life in this century: a newly-resurgent Islamism.

We saw the threat briefly, post-9/11, for what it was. We have since gone through more than a decade of gradual retreat from this view, which has ended in the wishful thinking that the threat is gone. Al-Qaeda is on the back foot, we told each other.

But It did not die. It merely shape-shifted, as we now see. The threat will not go until it is destroyed, while we are happily disarming willy-nilly across the developed world (as an aside, we might also note that at the same time Vladimir Putin has been doing the opposite).

We might ruminate on that, as we indulge in old internal battles over Iraq or congratulate ourselves on how we “stopped the rush to war” in Syria. Disarmament good, rearmament bad. But we have been asleep to the Islamist threat for too long. The principal threat is not, as is being widely reported, that of returning jihadis to the UK, although neither is that a pleasant prospect. The true threat is that the leaders of the nascent Caliphate will not be content until Western civilisation is damaged beyond repair.

This is not a drill. This is possibly the most important time in our lifetimes in terms of foreign policy that has a direct impact on our lives. We have to start thinking about the world as it is now, not how it was in 2003, and what we should do about it. We owe it to ourselves, and the rest of the world, not to just sit there with our arms folded.

This post first published at Labour Uncut, cross-posted at the Humanitarian Intervention Centre and selected for Progress’ What We’re Reading