Tony Blair’s message is simple: 9/11 was the beginning of the war, which continues and which we could lose if we are not mindful of the scale of the threat we face, and resolute in meeting it.

Blair likens the threat to the Cold War struggle against revolutionary communism. He describes how the West won the Cold War by demonstrating that (i) we were willing to use force to defend our way of life, and (ii) that our ‘idea’ beat communism. The analogy suits Blair, a big thinker who always excelled at distilling complex issues into sound bites and narratives. His implication barely needs to be spelt out: the threat may still be hidden to you, but this war against the forces of terror and religious extremism will define our future. We cannot afford to be complacent.

The ‘new Cold War’ lobby lacks a champion these days. Bush is serving a restrained retirement in Texas; Cheney and Rumsfeld recently published books, but neither man has any resonance outside his base. Blair was always the best communicator they had, and in the months before and after the invasion of Iraq he deputised as Bush’s Official Spokesman. Despatched to the far corners of the globe, a copy of the koran in his briefcase, he did his best to persuade the West’s allies to join the invading party. Although he failed to put together much of an anti-Saddam coalition, or perhaps because it proved so difficult to persuade his fellow world leaders to fall in line, Blair’s attachment to the idea that our civilisation is at stake has hardened ever since.

Blair accepts his views are unfashionable, and that the case for his brand of liberal interventionism is weaker than ever, even after Libya. Acknowledging the strength of hostility towards him, he asks his interviewer (John Humphrys) to “just accept the fact that there is another point of view”. This must be agony for Blair: he of all people knows where he stands in relation to public opinion. He no longer belongs in the mainstream, the fabled centre ground he found so quickly as Labour leader after 1994, and occupied so effortlessly until 9/11, and then fought to defend so aggressively.

You can see the weary smile as he says this, his uneven teeth, the raised eyebrows crashing his tanned brow. These days Blair is artfully turned out. He wears beautiful light weight suits (he has made 70 trips to the Middle East in the four years since he left Downing Street) and snow white shirts open at the neck. This is the uniform of the international rich, or the ageing crooner. He is lean from early morning sessions on hotel treadmills. For someone who won three elections, then retired, who has now made money, and who is able to maintain several successful enterprises which between them represent the causes he most values in the world, he looks and sounds remote and unhappy. Watch him interviewed on television and he seems uncomfortable. Perhaps he is weighed down by the anniversary. Perhaps he is just tired.

The interface between the private man and the public leader is fascinating, and Blair is a rich case study. There is the distance travelled between the guitar-playing social democrat and the prime minister closing his ears to the din of a million marchers while he prosecutes the case for an unpopular and costly war. And there is the religion, the Catholicism. Blair’s faith arcs over his transformation from fresh-faced student progressive to the hawkish defender of the free world with the 1,000 yard stare. All those people dead. Evil spreading like a stain across parts of the world. The soft bellies of the democracies. In the last decade Blair’s religious faith – something that was once hidden and, judging by his relaxed attitude to a series of moral issues, no more than a reflex – has overtaken him. Watch and listen to Tony Blair ten years after 9/11 and you will hear him frame things in terms of his belief – in the scale of the threat, in the need to meet it with might and resolution. Hear him explain that he believes Iraq was the right thing to do, that he believes we will prevail in Afghanistan, that we may have to attack Iran. He accepts that his views are unpopular, and that few share them, but this does not stop him believing. Listen to Tony Blair debate ’Is Religion a Force for Good’ with Christopher Hitchens in Toronto in 2010. The audience is stacked against him. And his argument is soft, founded on the the (undeniable) assertion that religious can inspire people to good works.

Good for Blair for debating Hitchens. He has courage. He has self-belief and he has faith. But he is wrong on the scale of the threat of radical islamism, and the way to go about countering it.