On 11 April 2017 Attorney-General Senator the Hon. George Brandis deliver a public lecture at the TC Beirne School of Law, University of Queensland, on the “The Right of Self-Defence Against Imminent Armed Attack In International Law”. While the doctrine of self-defence against imminent attack is well established at international law the Senator seeks to place the doctrine a modern context in which states must take account of non-state actors who have the capability to commit harm transnationally, and in which alongside the threat of terrorism by physical attack lies the threat of cyber attack. The key, according the Senator, is placing the word “imminent” in this modern context.

The speech consists in large part of an historical overview and a re-stating of the doctrine in its post-World War context. Australian, says the Senator, subscribes to the prevailing understanding of the doctrine. Under Article 51 of the UN Charter and international customary law the central point of the doctrine is that force may only be used in situations of armed attack or imminent armed attack:

Article 51

Nothing in the present Charter shall impair the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations, until the Security Council has taken measures necessary to maintain international peace and security.

The Article also requires nations exercising self-defence against an armed attack to report the attack to the Security Council. Two further developments in international customary law give the structure for Australia’s position on the doctrine of self-defence in a modern context.

First, the Senator cites a UN High Level Panel Report and the development of international customary law as making clear that the right to self-defence is triggered not only by an armed attack itself but also by an imminent armed attack. Second, the Senator then cites UN Resolution 1368 passed in the aftermath of the September 11 2001 attacks as the basis for widening the international customary law principle to one in which states are not confined to using force in self-defence against another state only.

The Senator then seeks to outline Australia’s approach to using the doctrine in the situation of terrorism or cyber-attack by highlighting the difficulties of implementing how a strictly traditional definition of the term “imminent” would prevent states from acting in the interest of their populations’ security in certain situations.

He uses the example where a terrorism cell has expressed an intent to cause harm to a state and then goes dark. This is an observed pattern which may indicate a future attack but it still remains difficult to tell how “imminent” an attack is, where it will occur or whether there may be some other unrelated reason for the communication going dark for a period.

In applying “imminence” to the doctrine of self-defence, according to the Senator Australia seeks to apply what are known as the “Bethlehem Principles”, enunciated by Sir Daniel Benthem QC (Sir Daniel Bethlehem KCMG QC, ‘Principles Relevant to the Scope of a State’s Right of Self‑Defense Against an Imminent or Actual Armed Attack by Non‑State Actors’ (2012) 106 American Journal of International Law 769). The principles concern the questions such as the probability of an attack, the scale of the anticipated attack, whether it is isolated or not and whether there will be other opportunities to defend against or avoid the attack.

The Senator also makes clear that the doctrine of self-defence must also be tempered by necessity, proportionality and the clear point of differentiation between self-defence as anticipatory to an imminent attack and self-defence as pre-emptive to an attack. The difference as he puts it is that pre-emptive self-defence is responding to “threats which have not yet crystallised but which might materialise in the future”. This is the line of demarcation in applying the doctrine in the context of terrorism and cyber-attack. The Senator quotes Livy in stating Australia’s unequivocal opposition to pre-emptive self-defence: “Men, to guard against their alarms, make themselves objects of terror; averting the danger from their own heads, by imposing upon others the necessity of either doing or suffering the evil which they themselves fear.”

Adherence to anticipatory self-defence rather than pre-emptive self-defence, the Senator says, allows Australia to act “from a position of legal authority and moral strength”. As the Senator himself highlights, the tensions in anticipatory self-defence are truly difficult, and future challenges will demonstrate whether Australia can reconcile its doctrine with its practice.