This is the true lesson of both Iraq and Afghanistan.

But it doesn`t mean that it is right to keep the dictator in place. Or possible. Because the lesson of what used to be called the "Arab Spring" -- beginning in 2011 -- is that with young and alienated populations deprived of political rights, these dictatorships no longer had the capability of maintaining control.

The real choice for the Middle East was, and is, reform or revolution. So when we come to reassess Iraq, it is possible to disagree strongly with the decision to remove Saddam Hussein in 2003, to be highly critical both of the intelligence on WMD and the planning for the aftermath, and yet still be glad that he is gone.

Indeed, had he and his two sons been running Iraq in 2011 when the regional revolts began, it is hard to see how the upheaval would not have spread to Iraq and hard to see that he would not have behaved like his fellow Baathist Bashar al-Assad rather than like the presidents of Egypt or Tunisia who stood down. The probability is that Hussein would have tried to cling to power by whatever means no matter how brutal.

In Iraq, we would have had a leader from the Sunni minority keeping out the Shia majority; in Syria, of course, we have the opposite -- a Shia-backed leader from the minority keeping out a Sunni majority. The consequences of this would have been vast.

Of the four nations in a state of trauma today in the region -- Syria, Iraq, Yemen and Libya -- only one has a government that is fighting the Islamic State of Iraq and Syria (with whatever difficulty), is doing so with full international support, has its leader recognized by both Saudi Arabia and Iran, and one who visits the White House.

It is correct, as Fareed Zakaria`s documentary describes, that Iraq has been hugely expensive in lives lost and money spent. I understand completely the anger and anxiety this causes.

But we do not yet know the cost of Syria or Libya. In both cases, we sought regime change. And in Libya we achieved it through military power. I make no criticisms of these decisions. I know better than most how hard they are.

However, it is not immediately plain that policy on Libya and Syria has been more successful than Iraq. As for ISIS, it is true that it was formed after Hussein`s removal. But it is also true by 2009, al Qaeda and other jihadist groups were largely beaten in Iraq, and it was in Syria -- after 2011 -- where ISIS came to prominence and became the threat it is today.

I accept some of the strictures about the planning in Iraq, which had centered on the consequences of humanitarian disaster post-invasion and what would happen to the institutions of the country or if Hussein used WMD. But, part of the reason why Iraq became very difficult was that we did not perceive the full scale of the underlying extremism and its attendant violence. Where this type of extremism operates, there is a limit to what planning can do. They need to be fought against.

Underlying all of this is something Western policy is not yet wanting to admit: There is a deep-rooted problem originating in the Middle East -- the product of a toxic mix of abused religion and bad politics -- that has given rise to an ideology based on radical Islamism and that is now a global challenge.

Of course, some will say we should never have gone into Iraq because that gave the extremists an opportunity. But my point is that had we never removed Hussein, it is not at all clear that we would be in a better position today post-2011 -- or that he would not have used the erosion of sanctions (and, back then, $100 a barrel oil) to go back to his old games.

Not until the Middle East has gone through its painful transition to modernity will we be able to pass a full judgment on the effects of decision to go to war in 2003.

But when I think of the hundreds of thousands of victims of Hussein -- the bloodshed and instability his wars caused the region and his people -- then, for all the mistakes that were made and for which those of us involved have always apologized, I think history will be more balanced in its judgment.

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