Former British prime minister Tony Blair has called for a global compact to remove extremism and Islamist political influence from schools.

And while the defeat of ISIL in Raqqa and Mosul proved significant in the battle against terrorist groups, Mr Blair warned that the threat remains strong.

“The threat is very real,” he told The National at his London offices. “We focus on ISIL but there is still Al Qaeda and a plethora of groups throughout the world, such as Al Shabab, Boko Haram ...

"You have to tackle the ideology, not just the violence, because it is the thinking that gives rise to the violence. You have to hit at the extremism in thought and in deed if you want to tackle this thing properly."

The former Labour leader led the country after the 9/11 atrocities in the US and was a prime architect of the war to overthrow Iraq's Saddam Hussein in 2003. During his term, Britain faced its worst modern terrorist attack when buses and tube trains were hit, killing 52, in London on July 7, 2005.

“There should be some global commitment around education systems where governments undertake a commitment to promote religious tolerance and root religious prejudice from their systems, formal and informal,” Mr Blair said.

“Education, in my view, in many countries is a security issue. There are millions of young people who are being educated every day to a view of religion that is wrong and also extreme.

"You see this in schools were the Muslim Brotherhood and others have a strong grip and if you educate young people to these extreme views, don’t be surprised if some of them turn out to become violent."

He said authorities needed to tackle informal madrassas, or Islamic schools, and other unregulated centres of learning, not just in Muslim-majority countries but also in Britain and elsewhere. A comprehensive, global strategy is needed.

“I think there is a great opportunity to build an alliance between open-minded Muslim-majority countries and the West because we’ve got the same problem, the same challenge," Mr Blair said.

"The big change today is there is leadership coming from the Emirates, from Saudi, from Egypt, from Jordan, Bahrain, to put forward a view that is rational and open-minded about the role of religion in society.”

On whether the British government will, or should, designate the Muslim Brotherhood as a terrorist organisation, he said: "That debate will carry on depending on what they do in individual countries, and it can differ.

"What is beyond contention is that if you take any religion and you turn it into an exclusive, politicised, ideology so that it is effectively a totalitarian ideology - you say this view of religion should govern society, and government - then you have a problem. The politicisation of Islam is the root of the problem and it is not something that goes back centuries.

Tony Blair is interviewed by Mina Al-Oraibi, Editor in Chief of The National, and London Bureau Chief Damien McElroy. Stephen Lock for the National

“We have been blind to this in some of our own communities, where we have woken up. But it is impacting the politics of the whole of Europe now, if you look at the recent elections in Austria, for example. This is a major factor."

Mr Blair said that "the risk is if we don’t deal with it then our public in the West becomes so angry about the failure of the political system to deal with what they see as a real problem that they become anti-Islam - and not anti-Islamism as a political ideology.”

The collapse of the political centre as European and American parties turn to the left and right for leadership polarised the debate and left extremisms to flourish.

“Parts of the liberal left don’t want to see the problem,” Mr Blair said. “You even get to my mind absolutely bizarre alliance between Muslim Brotherhood-type groups in the West and left-wing politics. It's just crazy. Then on the right you get people who want to exploit this issue. To them, it is about saying Islam is the problem.”

Part of this is related to identity. "If dealt with in the correct way, it allows you to say ‘I have my own religious beliefs but when it comes to my citizenship, I am part of the common space’. And that should be true of Muslims, Jews, Christians, Hindus or any other religion."

Mr Blair acknowledged that some Muslims in Europe felt that they were being stigmatised.

"We have to be honest about this, there is a problem within small parts of Muslim communities in our countries, and if we don’t deal with it, people start to think it is about Muslims."

Mr Blair has reorganised much of his post-Downing St role but retains a strong focus on analysing radicalisation and fighting extremism. He warns that countries are still losing the battle of propaganda against outfits such as ISIL and Al Qaeda.

"Wherever the propaganda of these extremists is being promoted, you have got to be able to stop it," he said. "A lot of the ways we tackle extremist websites is inadequate, a lot of key words we are missing.

"It is very important to be diverting a lot of the people who come on to those sites, not just closing them down, but diverting people who come on to them into more positive material.”

He praised the UAE's trailblazing framework for tackling radicalisation, saying it was a model for others. “A lot of the work in Abu Dhabi and indeed elsewhere is really important in showing people there are better, different interpretations of Islam.”

Mr Blair said that in the regional countries struck by violence and internal strife, such as Iraq, Syria, Libya and Yemen, sectarian politics and corruption are are root causes.

"Wherever you look, it is essentially the same questions that arise: can you establish a politics in which there is an acceptance that politics cannot operate on sectarian lines? There is no way you can keep the politics of the country together unless there is some understanding that sectarianism cannot be the basis of the political system.

"If you want to create stable politics, you have got to have a stable basis for the economy to grow and that depends on rule-based economies where corruption is ruled out.

Tony Blair led the country during the aftermath of the 9/11 atrocities in the US and was a prime architect of the war to overthrow Saddam Hussein in 2003. Stephen Lock for the National

"Having a functioning, independent state means that those powers who want to push you in a sectarian direction have to be pushed out. In Iraq’s case, this is Iran."

He said the Iraqi prime minister, Haider Al Abadi, "genuinely wants to operate according these principles, and for all of Iraq’s problems at least you have a prime minister considered legitimate by Saudi Arabia and Iran, and the job of the West is to support him in achieving those principles".

"The risk very clearly at the moment is if Iran wants to turn Iraq into a proxy state. This would be a disaster for Iraqis and it will not lead to a cohesive society or politics, and it won’t lead to a good economy."

When the uprising in Syria started in 2011, many who were opposed to an intervention against Syrian president Bashar Al Assad pointed to Iraq as the example of a failure of western intervention.

"When Syria erupted in 2011, I argued strongly at the time that you should sit down with Assad and agree some process of transition," Mr Blair said. "But if you are not going to do that and you are insisting that he goes, then go get him out."

He said that the error was to "insist he goes and then leave it there, then you leave no way out but to fight". Now, Mr Blair says "there is no good solution in Syria, so I am in favour of whatever can practically work at this point and the powers that are exercising enormous influence in the country are going to have to find a way out of this, and so the relationship between America and Russia is extremely important".

"The events of the last six years mean that people have to feel they have a say in the running of the country, but if they feel the Syrian regime is just a puppet of the Iranian regime they are never going to feel that. The leading powers need to come to an agreement, and the principles I outlined [for Iraq] are also needed in Syria."

So how could the chaos in Iraq, Libya or Syria have been avoided?

"The answer to any of these situations was not to have kept Saddam there or [Libyan leader Muammar] Qaddafi there. However, once you remove the dictatorship you have to hold in there. The only way we are going to get a decent outcome in Syria or in Iraq is if the United States is committed. To be fair, this administration is making a commitment. It is the commitment that gives you bargaining chips at the table.

Mr Blair said that at one stage, the situation in Iraq could have been salvaged, if not for diminishing commitment by the US and the sectarianism of the Iraqi government. "Then the Arab Spring happened."

He admitted that British resolve to fix the situation had also decreased at that time. "British and American commitment often go together."

He also linked between what happens in the Middle East and Europe: "What is happening in our countries and the region is all together. A struggle for a view about the way societies operate that is essentially open-minded and tolerant."

Mr Blair acknowledges that some may be sceptical of his remarks because of his leadership in the 2003 war in Iraq. But he does not back away from questions about his decision.

Tony Blair said the UAE continued to be the most appealing destination for young Arabs. Stephen Lock for the National

"It is never for the history books, there are live questions today," he said. "I answer this all the time. What people want is for me to say I wish I left [Saddam] there in 2003 and I won’t say that because I don’t believe it.

"I have learnt that there is no point re-litigating this. And in the region itself there is a clearer understanding that these problem are deep rooted."

Mr Blair said the leadership emerging in some of the region's countries today was refreshing. "And you can see this in what the UAE has created, a decision by certain leaders in the region that our destiny lies in our own hands. Ultimately, making a success of our country depends on us."

He said the UAE continued to be the most appealing destination for young Arabs because "there is a strong and stable system of government, the country is going places. It is modernising. It is moving in a direction of greater tolerance, greater equality between men and women and this is the future".

He was also impressed by the emergence of Saudi Crown Prince Mohammed bin Salman, which he described as "the single most important event in its potential significance for the region in the last few years. Mr Blair said this was because Prince Mohammed "has a strong, clear, modernising vision for Saudi Arabia and because he can lead the country to a place it should be, which is a powerhouse in the region, economically and politically".

For his home country, Mr Blair called for a vote on Britain’s “divorce deal” with the European Union that could reverse the decision to leave if the terms on offer were unfavourable.

“We knew what we were voting against last June but we can’t possibly know until we do the deal what is the future,” he said. “It's agreeing a house swap before you’ve seen the other house. What’s very important from a British perspective is that we don’t have a vote on the divorce until we see the terms of the new relationship. To take a view of this you need to be able to see both sides of the equation."

Would that mean another referendum that cancels last year's vote? “It is an open question. It could be an election, it could be a referendum. The principle is you have to have a final say.”

One of the Brexit sticking points for Mr Blair is that Britain is leaving a powerful global bloc at a time of global concentration of power. He has been one of the greatest advocates for a strong relationship with the United States, despite questions about the leadership of president Donald Trump's administration.

"American leadership is still going to remain fundamentally important but the West needs to understand that the world is changing in a very big way. We are finally waking up to the fact that the dominant relationship in the 21st century will be America’s relationship with China. The most important thing in my mind is that America and Europe remain strong and remain together.

"I am an optimist on China, but it is the fact of China - its size, population three times the size of the EU -- it is a fact you must take into account.

“[This is] one of the reasons why I am so passionately against Brexit for a country like Britain. The only way countries of any size - below 200 million as it were - are going to be able to exercise influence and weight is by allying with others and the most obvious are regional alliances.”

One of the great achievements of Mr Blair’s 10 years in office was the Good Friday Agreement, which brought peace to Ireland and removed the border with the British-run north. Brexit puts that achievement in jeopardy.

“Brexit is the determining issue of our time for the UK,” he said. “With Northern Ireland, Brexit imposes a strain on the UK. With Scotland, it will depend on what happens over time.”

As prime minister, Mr Blair was a champion of devolution to Scotland, which led to a failed referendum for independence. While he sees that 2014 vote and the recent informal Catalan independence referendum as a reaction to the drift of power upwards to supra-national bodies, the same dynamic cannot be said to be at work in the Kurdish dispute with Iraq. That stems from internal disputes with the Iraqi Kurds.

“The Kurdish issue is different - they have different populations in different countries,” he said. “They have had legitimate anxieties about the central government in Baghdad and I hope all this can be resolved in a good way.

"The positions of Scotland and Catalonia are different. it is a reaction against a surpra-nationalist power."

But Mr Blair warned: ‘You are never going to become more powerful or more capable by getting yourself out of the relationship you have."