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Al Qaeda’s Nuclear Ambitions

Ayman al-Zawahiri promises to make his next smoking gun a mushroom cloud.


American authorities managed to foil al Qaeda’s latest plot to attack — via hidden explosives in mail parcels — but the long-term question remains unanswered: How can they ensure that they stay one step ahead of the terrorist group?

The good news is that there’s no need to wonder what the terrorists’ strategic and tactical goals are — one need only listen to what their leaders have already told us. The bad news is that we no doubt won’t like what we hear. Al Qaeda’s leaders yearn to acquire and use weapons of mass destruction against the United States; if they acquired a nuclear bomb, they would not hesitate to use it. Indeed, such an attack would be meant to serve as a sort of sequel to the 9/11 plot.

The evidence for those intentions aren’t hidden in encoded communications or classified intelligence. Quite the opposite: They’re hidden in plain sight. Just as Osama bin Laden issued a fatwa to declare war on the United States in 1998, his deputy, Ayman al-Zawahiri, issued a fatwa a decade later to herald a prospective next stage in the conflict. If we take him at his word, some day jihadists will use weapons of mass destruction to change history once and for all.

Of course, al Qaeda leaders have spoken of acquiring weapons of mass destruction for well over a decade. They have had little observable success in achieving their goals of producing a nuclear bomb or biological weapon capable of producing mass casualties. Fortunately, it is extremely difficult, but not impossible, for a terrorist group to acquire a strategic weapon of mass destruction (WMD). Nonetheless, the al Qaeda core has kept at it over the years, in the hopes that time and opportunity will enable it to overcome the daunting challenges in this regard.

What has changed recently is that the goal is no longer theoretical, but operational — a change spurred by Zawahiri’s intervention. Rather than follow bin Laden in issuing a religious edict, Zawahiri chose to release a book in 2008 titled Exoneration. In it, he resurrects a fatwa issued by senior Saudi cleric Nasir al-Fahd in May 2003 — notoriously, the only such treatise that ever endorsed the use of WMD. Zawahiri adopts Fahd’s ideas wholesale. He uses the same ideas, thoughts, examples, and scholarly citations to reach the same conclusion: The use of nuclear weapons would be justified as an act of equal retaliation, “repaying like for like.”

Zawahiri raises key Quranic themes to sweep away all potential objections to the use of WMD. He offers answers to questions about the legality of killing women, children, and the elderly; the justice of environmental destruction; the morality of harming noncombatants; the tactical prudence of attacking at night; and analyses of deterrence. Zawahiri adopts Fahd’s examples verbatim: The Prophet Mohammed’s attack on the village of al-Taif using a catapult, for instance, permits the use of weapons of “general destruction” incapable of distinguishing between innocent civilians and combatants.

The take-away from Zawahiri’s book is that the use of weapons of mass destruction should be judged on intent rather than on results; if the intent to use WMD is judged to be consistent with the Quran, then the results are justifiable, even if they clearly violate specific prohibitions under Islam. The same reasoning is applied in a detailed explanation of such matters as loyalty to the state, contracts, obligations, and treaties; the permissibility of espionage; and deception and trickery. For example, on the topic of Muslims killed in combat unintentionally in the fight against infidels: “When Muslims fight nonbelievers, any Muslim who is killed is a martyr.”

Aside from its general endorsement of WMDs, we should pay special attention to two operational messages embedded in Zawahiri’s book.

First, America is a special object of Zawahiri’s attention when discussing a nuclear attack. Zawahiri explicitly ties U.S. crimes to the alleged need to use WMD, quoting Fahd: “There is no doubt that the greatest enemy of Islam and Muslims at this time is the Americans.”

Zawahiri further explains that he considers the United States to be a “single juridical entity” under Islam. It’s a verdict with chilling implications: Zawahiri means to say that all Americans are valid targets, regardless of whether they are men, women, or children. This is not a mere aside; it is a careful choice of words that reflects a seriousness of purpose.

Indeed, he is at pains to prove his judiciousness. He cites a variety of viewpoints from the Quran and hadiths (sayings of the Prophet Mohammed), some of which support his judgments, others which do not. At times, he dramatically prefaces his conclusion with the words “I say …” to draw attention to the fact that his judgments digress from the views held by some Islamic scholars; it is also a way for Zawahiri — a medical doctor, not a religious scholar by training — to assume authority for himself as an arbiter of Islamic law.

Second, al Qaeda has reckoned with the horrific scale of a nuclear attack; indeed, Zawahiri sees mass casualties as a point in WMDs’ favor. Zawahiri’s book explicitly justifies a potential attack that could kill 10 million Americans. Again, that enormous figure is not merely tossed off casually by Zawahiri. He believes that such a plan requires justification, and he is satisfied, at the conclusion of his book, that he has done so.

It is notable that Zawahiri repeatedly uses the phrase “artillery bombardment” in the context of discussing the wide-scale destruction of a WMD attack. For al Qaeda, it seems, modern weapons of mass destruction are simply a form of weapon that cannot distinguish between civilians and combatants. Nuclear weapons, Zawahiri wants to argue, are no more morally significant than the catapult often cited in the Quran and hadiths. Here Zawahiri quotes Fahd once again: “If a bomb were dropped on them, destroying 10 million of them and burning as much of their land as they have burned of Muslim land, that would be permissible without any need to mention any other proof.”

Needless to say, Zawahiri’s approach goes against all Western theories of just war. Zawahiri’s dismissal of moral qualms in jihad echoes the words of his mentor, Islamist philosopher Sayyid Qutb: “The Islamic jihad has no relationship to modern warfare, either in its causes or in the way it is conducted.”

Zawahiri is a man of action, not contemplation, and his tone leaves little question that he believes the West has not yet been exonerated for its crimes. And like bin Laden in 1998, Zawahiri is not only a cleric but an operational planner — we can be assured that he is planning al Qaeda’s redemption by means of the terrible weapons he champions. Exoneration is a warning that the rules of engagement may be about to change. We would be foolish not to heed it.

Rolf Mowatt-Larssen is a senior fellow at Harvard Kennedy School's Belfer Center for Science and International Affairs. Prior to his appointment at Harvard, he led the government's efforts at the Department of Energy and the Central Intelligence Agency to find and track potential nuclear terrorists and to prevent a nuclear terrorist attack on the U.S. An expanded version of this introduction and timeline are available here.

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