That’s the big takeaway for the world’s media outlets from this lengthy essay by Tony Blair, and one can easily understand why. When the former leader of the British commonwealth and an architect of the 2003 Iraq War suggests that the West may have to go back on offense in the same theater, it rightly makes headlines. Even while attempting to soften the blow, Blair’s advice sends an unmistakable rebuke to leaders attempting to start off the fight against ISIS by circumscribing the potential options to deal with it properly:

“I accept fully there is no appetite for ground engagement in the West,” Blair wrote in an essay on the website of the Tony Blair Faith Foundation.

“But we should not rule it out in the future if it is absolutely necessary. Provided that there is the consent of the population directly threatened and with the broadest achievable alliance, we have, on occasion, to play our part.”

He added that air power alone “will not suffice” in the fight against the IS group.

“They can be hemmed in, harried and to a degree contained by air power. But they can’t be defeated by it,” Blair added.

“You cannot uproot this extremism unless you go to where it originates and fight it.”

Blair sees this more clearly than most, but not all. The Pentagon wants to keep the ground-forces option open too, and find themselves hamstrung by Barack Obama’s repeated pledges to refrain from it:

As America re-engages with Iraq and deepens its involvement in the region’s web of sectarian conflicts, the Pentagon has made a practical assessment of the brutal job of stabilizing Baghdad: in the future, U.S. forces may be needed on the front lines.

President Barack Obama has ruled out a combat mission, but military officials and former officials say the reality of a protracted campaign in Iraq and possibly Syria may ultimately require greater use of U.S. troops, including tactical air strike spotters or front-line advisers embedded with Iraq forces.

That raises questions over how far Obama can go in the expanding U.S. military power without appearing to violate promises not to drag America into another ground war and highlights different priorities between the White House and Pentagon at the start of what looks to be a long, unpredictable military campaign in Iraq and Syria.

From a military perspective, officials say it makes sense to at least have the option of deploying small numbers of U.S. military advisers alongside Iraqis on the front, time-to-time, even if that appears to contradict Obama’s stated policy.

This gets back to what Chuck Todd noted over the weekend — that there are major disconnects in American policy-making. Obama is approaching the conflict with ISIS in the context of domestic American politics, while the Pentagon approaches it from the perspective of a military and ideological conflict. It may not be necessary to send American ground troops to fight ISIS, but it will take ground troops of sufficient strength, morale, and armament to defeat ISIS and retake the ground they’ve seized. If we cannot get sufficient ground strength from other sources, then either the West will have to fill the gap or give up on defeating ISIS.

Blair rejects that option altogether:

The first is that it is hard to envisage compromise with such people. They have no reasonable demands upon which we can negotiate. This is not like Irish Republicanism. There may be individual conflicts – like the Mindanao dispute in the Philippines – where there can be a peace agreement reached because the primary cause of conflict is local. But in general, though political engagement can reduce the support and freedom of manoeuvre of the fanatics, or divide off the merely disaffected, as was the case in Iraq up to 2010, there is no alternative to fighting and defeating the hard-core.

At a certain point, once they know superior and determined force is being used against them, some of them at least may be prepared to change. And some undoubtedly have taken up arms because of genuine grievances. So yes it is true that in Iraq after 2006, as a result of the ‘Awakening’, the political process that brought the Sunni tribes to an understanding with the Government was crucial. However so was the surge; so was the day after day, night after night, war of attrition and suppression waged with such courage by US, UK and other forces.

The second is that the moment they cease to be fought against they grow; and fast. ISIS now controls a territory in Syria and Iraq larger than the size of the UK. Just think about that, let its full ghastly implications sink in. This is right on the doorstep of Europe. Boko Haram was reported recently to have taken the Northern city of Bama in Nigeria. Weapons from Libya together with funding have increased their reach and firepower. Libya itself is in the grip of warring factions where the risk is not just the vanquishing of internal stability, but the export of arms, money and extremist personnel across the world. As fighters are pushed out of Yemen, they go across to Somalia and from there across west to the northern parts of Sub-Saharan Africa. With territory comes the opportunity for these groups to gain money through extortion and kidnapping, to access resources, and build manpower.

The third is that whilst terror is upright and busy, it is impossible for any country to solve its everyday challenges and embrace with confidence the future. It is not simply the act of terror and the fact of carnage that de-stabilises a nation. It is the fear, the chaos, the tremor throughout the whole of society, deepening fault-lines, exacerbating existing divisions and giving birth to new ones. That is why it has to be fought against with vigour and without relenting.

Fourth and hardest of all, because the enemy we’re fighting is fanatical, because they are prepared both to kill and to die there is no solution that doesn’t involve force applied with a willingness to take casualties in carrying the fight through to the end.

Blair also argues for the West to recognize that Islamism is a spectrum, and it’s not a fringe, either:

The problem is not that we’re facing a fringe of crazy people, a sort of weird cult confined to a few fanatics. If it was, we could probably root it out, kill or imprison its leaders, deter its followers and close the doors to new recruits.

The problem is that we’re facing a spectrum of opinion based on a world view which stretches far further into parts of Muslim society. At the furthest end is the fringe. But at the other end are those who may completely oppose some of the things the fringe does and who would never themselves dream of committing acts of violence, but who unfortunately share certain elements of the fanatic’s world view. These elements comprise, inter alia: a belief in religious exclusivity not merely in spiritual but in temporal terms; a desire to re-shape society according to a set of social and political norms, based on religious belief about Islam, wholly at odds with the way the rest of the world has developed, for example in relation to attitudes to women; a view of the West, particularly the USA, that is innately hostile and regards it essentially as the enemy, not only in policy but in culture and way of living.

This Islamism – a politicisation of religion to an intense and all-encompassing degree – is not confined to a fringe. It is an ideology (and a theology derived from Salafist thinking) taught and preached every day to millions, actually to tens of millions, in some mosques, certain madrassas, and in formal and informal education systems the world over.

It is the spectrum that helps create the fringe. A large part of Western policy – and something I remember so well fighting in Government – is based on the belief that we can compromise with the spectrum in the hope of marginalising the fringe. This is a fateful error. All we do is to legitimise the spectrum, which then gives ideological oxygen to the fringe. …

So we may naturally prefer to see these people who have come to our attention in the last weeks as isolated lunatics, to be hunted down like serial killers and with their demise the problem is eradicated. Would that it were so. But it isn’t. Unless we confront the spectrum as well as the fringe, we will only eliminate one group and then be faced with another.

Blair’s missive is worth reading in its entirety. It is filled with a forgotten wisdom from years of dealing with the same issues while serving as Prime Minister, and it provides an antidote to some of the ignorance which has abounded over the last few years. Interestingly, and perhaps counter-intuitively (and certainly counter-consensus-ish), Blair rejects the self-blame in which the West engages over Sykes-Picot and the post-Versailles period, and advises everyone to quit worrying over spilt milk and get re-engaged with reality now.

Will Blair’s advice be taken in the capitals of the West? Perhaps not, but at least it will be heard.