Osama Bin Laden By Michael Scheuer. Oxford University Press, paperback. 278pp with index. Available from Amazon, Us$13.00

With the secular, pro-Western government in Tunis having fallen and the regime in Cairo then followed suit, the timing of Michael Scheuer's new biography of Osama bin Laden may seem a little off.

For where have the Islamists been in all this, let alone jihadis of any stripe? People power appears to have succeeded where al-Qaeda's murderous violence has not. But Scheuer, the first head of the CIA's bin Laden unit from 1996-99, thinks that the object of his scrutiny will be delighted.

"It's always been one of his primary goals to get rid of those who he sees as oppressors and apostates and dominate the region," Scheuer said recently while publicizing his book. "I'm sure this is very welcome news for him."

It is far too soon to tell what role Islamist groups will play in the wave of change in the Middle East. Scheuer, however, would warn against taking their current absence from the stage as a reason to regard al-Qaeda not only as "an organisation of thugs led by a sociopath" who have "dwindled to a few" but now also as marginal extremists who have been overtaken by history.

On the contrary, he proclaims in his preface, "the United States remains largely undefended... the American government and most of its European peers are running the war against al-Qaeda and its allies in a manner best designed to help the Islamists achieve victory."

The current strategy, he says, is pushing America to bankruptcy, weakening US military reach and power, and isolating it from its former friends. In fact, according to Scheuer, almost everything the West is doing, right down to using the word "extremist" to brand bin Laden and his followers, is wrong.

Why should we listen to him? Well, Scheuer's career in counter-terrorism is one reason, as is the fact that he has a prominent voice in the American public square. An even more compelling reason is that bin Laden himself commended his previous book, "Imperial Hubris," in a 2007 statement: "If you want to understand what's going on and if you would like to get to know some of the reasons for your losing the war against us, then read the book of Michael Scheuer in this regard."

Part of Scheuer's work – dismissing the myths that bin Laden is an agent of Iran, or of the Pakistani ISI – are easy. Other areas, such as whether al-Qaeda exists as a structured international organization as opposed to being a weak center with little or no control over its "franchise" operations in the Maghreb or the Arabian Peninsula, for instance, are more contested. Scheuer makes the case that al-Qaeda does have a functioning chain of command, although his use of Iraq as an example – where the Jordanian militant Abu Musab al-Zarqawi pretty much went rogue – leaves the impression that while the center has influence and contact, it cannot be sure of enforcing its wishes.

He also argues convincingly that bin Laden should not be viewed as some pliant idealist, elevated to a position of authority only because of the wealth derived from his family's construction business in Saudi Arabia, and whose mind was turned from the legitimate fight against the Russians in Afghanistan to a crazed war on all infidels by his evil No. 2 from Egyptian Islamic Jihad, Dr Ayman al-Zawahiri. Bin Laden, writes Scheuer, "is not the caricature that we have made of him." Instead, he is, "pious, brave, generous, intelligent, charismatic, patient, visionary, stubborn, egalitarian, and, most of all, realistic – he is a man who has grasped the timeless truth that wars are only won by killing."

Scheuer may well be right about the first nine adjectives – he provides plenty of material to justify their use – but the last, "realistic," and his explanation for its inclusion, lead to the most controversial part of his analysis. The point above all that Scheuer wants the reader to grasp, is that Osama bin Laden is in no way a deviant Muslim but one whose actions and plans are fully informed by religious teachings and backed by scholars – and is thus widely regarded as a hero, a new Saladdin, by a large part of his fellow Muslims.

Just how large is moot here. Scheuer's view is not just that jihad is a religious duty – that in itself is not a remarkable contention – but that the interpretation of the term put forward by many, "a vigorous but peaceful endeavor through which the individual Muslim struggles first to control himself and then to master his baser tastes and inclinations", as he puts it, "is an indefensible position".

For him, jihad is primarily military and any suggestion that most Muslims do not think of it in this way is dangerous nonsense. Extremely dangerous, if one agrees with his assertion that al-Qaeda "has the potential to mobilize thousands, perhaps millions of the world's 1.3 billion Muslims by applying an interpretation of Islam which, alone, encompasses the obligation to fight among its tenets."

Scheuer's intention is for us to understand the real bin Laden, not the swivel-eyed lunatic it suits us to portray him as. He is right to say that too often the West's reaction to bin Laden has been "if only Osama (and implicitly all Muslims) were more like us Westerners." On the other hand, Scheuer has fallen into the opposite trap of imagining that the vast majority of Muslims are very much like, or at least highly sympathetic to, bin Laden. Rather a lot of the 250 million Muslims who live in South East Asia would beg to differ, I would suggest.

The strange thing is that Scheuer appears to want this to be so. On many points he is extremely sharp, clarifying, for instance, that bin Laden's anti-US defensive jihad has been primarily about the removal of US troops and influence from the Muslim world, and not about turning Western countries into Islamic states. "The reality was that as long as the West did not try to impose its decadence – for which many Muslims considered ‘democracy' a synonym – in the Islamic world, Muslims would live and let live; few were or are willing to die in a jihad against congressional elections, gender equality, R-rated movies or Budweiser."

But he wholeheartedly accepts, indeed, propagates, the line that the most extreme and violent interpretations of Islam are recognized as religiously valid by all, save for a few scholars compromised by collusion with the Gulf monarchies and, one assumes, the nonobservant and the liberal who still regard themselves as Muslim.

It is a deeply pessimistic view of Islam and one that, if correct, might justify his conclusion: "We are fighting a war for survival; if we do not win outright and irrefutably, we will surely lose in the same manner."

One can understand why Osama bin Laden thinks Scheuer is right. The rest of us, who would rather applaud Muslims who emphasize the pacific aspect of their religion and those who wish to embrace democracy, must hope he is wrong. When it comes to defining what Islam in its multifarious forms actually is, the real danger would lie in taking Osama's word for it. Scheuer does. We must hope not too many of his compatriots do.