Tony Blair - Iraq, Syria and the Middle East.

Easily the most likely scenario is that Iraq would have been engulfed by precisely the same convulsion. Take the hypothesis further. The most likely response of Saddam would have been to fight to stay in power. Here we would have a Sunni leader trying to retain power in the face of a Shia revolt. Imagine the consequences. Next door in Syria a Shia backed minority would be clinging to power trying to stop a Sunni majority insurgency. In Iraq the opposite would be the case. The risk would have been of a full blown sectarian war across the region, with States not fighting by proxy, but with national armies.

The problems of the Middle East are the product of bad systems of politics mixed with a bad abuse of religion going back over a long time. Poor governance, weak institutions, oppressive rule and a failure within parts of Islam to work out a sensible relationship between religion and Government have combined to create countries which are simply unprepared for the modern world. Put into that mix, young populations with no effective job opportunities and education systems that do not correspond to the requirements of the future economy, and you have a toxic, inherently unstable matrix of factors that was always – repeat always - going to lead to a revolution.

But because of the way these factors interrelate, the revolution was never going to be straightforward. This is the true lesson of Iraq. But it is also the lesson from the whole of the so-called Arab Spring. The fact is that as a result of the way these societies have developed and because Islamism of various descriptions became the focal point of opposition to oppression, the removal of the dictatorship is only the beginning not the end of the challenge. Once the regime changes, then out come pouring all the tensions – tribal, ethnic and of course above all religious; and the rebuilding of the country, with functioning institutions and systems of Government, becomes incredibly hard. The extremism de-stabilises the country, hinders the attempts at development, the sectarian divisions become even more acute and the result is the mess we see all over the region. And beyond it. Look at Pakistan or Afghanistan and the same elements are present.

Understanding this and analysing properly what has happened, is absolutely vital to the severe challenge of working out what we can do about it. So rather than continuing to re-run the debate over Iraq from over 11 years ago, realise that whatever we had done or not done, we would be facing a big challenge today.

Indeed we now have three examples of Western policy towards regime change in the region. In Iraq, we called for the regime to change, removed it and put in troops to try to rebuild the country. But intervention proved very tough and today the country is at risk again. In Libya, we called for the regime to change, we removed it by airpower, but refused to put in troops and now Libya is racked by instability, violence and has exported vast amounts of trouble and weapons across North Africa and down into sub- Saharan Africa. In Syria we called for the regime to change, took no action and it is in the worst state of all.

However more than that, in this struggle will be decided many things: the fate of individual countries, the future of the Middle East, and the direction of the relationship between politics and the religion of Islam. This last point will affect us in a large number of ways. It will affect the radicalism within our own societies which now have significant Muslim populations. And it will affect how Islam develops across the world. If the extremism is defeated in the Middle East it will eventually be defeated the world over, because this region is its spiritual home and from this region has been spread the extremist message.

There is no sensible policy for the West based on indifference. This is, in part, our struggle, whether we like it or not.

Already the security agencies of Europe believe our biggest future threat will come from returning fighters from Syria. There is a real risk that Syria becomes a haven for terrorism worse than Afghanistan in the 1990s. But think also of the effect that Syria is having on the Lebanon and Jordan. There is no way this conflagration was ever going to stay confined to Syria. I understand all the reasons following Afghanistan and Iraq why public opinion was so hostile to involvement. Action in Syria did not and need not be as in those military engagements. But every time we put off action, the action we will be forced to take will ultimately be greater.

The starting point is to identify the nature of the battle. It is against Islamist extremism. That is the fight. People shy away from the starkness of that statement. But it is because we are constantly looking for ways of avoiding facing up to this issue, that we can't make progress in the battle.

Of course in every case, there are reasons of history and tribe and territory which add layers of complexity. Of course, too, as I said at the outset, bad governance has played a baleful role in exacerbating the challenges. But all those problems become infinitely tougher to resolve, when religious extremism overlays everything. Then unity in a nation is impossible. Stability is impossible. Therefore progress is impossible. Government ceases to build for the future and manages each day as it can. Division tears apart cohesion. Hatred replaces hope.

We have to unite with those in the Muslim world, who agree with this analysis to fight the extremism. Parts of the Western media are missing a critical new element in the Middle East today. There are people – many of them – in the region who now understand this is the battle and are prepared to wage it. We have to stand with them.