A state need not wait to absorb an attack it can see coming

The argument

Proponents of this position argue that the right of self-defence would be worthless if it could only be exercised after the damage was done. A state that watches an adversary mobilise, arm and declare its intent, and is nevertheless required to wait until the first blow lands, is being asked to sacrifice its people to a formality. Self-defence, on this view, is a right to protect against an attack, not a right to retaliate for one, and protection necessarily involves acting before the harm occurs. The argument is strengthened, proponents hold, by what modern weapons have done to the time available. When attacks took weeks to arrive and could be met at the border, waiting cost little. Against weapons that can be delivered in minutes and cannot be intercepted reliably, the first strike may also be the last; a state that defers until an attack is under way may have no capacity left with which to defend itself. Proponents argue that a rule written for an earlier technology should not be read so as to guarantee defeat under a later one. Proponents also press the consequences. Threats that are left to mature usually become more costly to deal with, not less: the adversary acquires more capability, better positions and more allies, and the eventual war is longer and bloodier than an early intervention would have been. Where that trajectory is clear, acting first can be the course that saves the greater number of lives on both sides. Because self-defence must include protection against foreseeable attack, and delay can make a state defenceless or make the eventual war far worse, this argument concludes, preventive war can be justified.

Premises

Counter-arguments

Opponents reply that the attack said to be coming is precisely what the war makes unknowable, so the justification can never be tested: if nothing happens the action is called a success, and if the intelligence was wrong the war has already occurred. They add that such assessments are produced in secrecy under political pressure and are frequently mistaken, and that every state which has attacked another has described it as forestalling a danger.

Rejecting the premises

[Rejecting P1] Self-defence as recognised in law and in most moral accounts is defence against an attack under way or imminent, which is precisely what separates it from prevention. The premise collapses pre-emption against an imminent attack into prevention against a future one, and it is the second that requires justification. [Rejecting P2] Speed of delivery is a reason to harden defences, improve warning and maintain deterrence. The premise does not show that striking first is the only remaining option rather than the earliest available one. [Rejecting P3] That threats generally become more costly to confront assumes they mature rather than dissipate, and it is offered as a tendency without the comparison it needs: the cost of wars begun on predictions set against the cost of the attacks those predictions foresaw.