Q. Can any modern war be regarded as a “just war” (Aquinas’ phrase) or a “permitted war” (to use the Talmudic terminology)?
The concept of war was always difficult. The Bible did two things at once. It reported wars and believed there were wars which God would approve; it also yearned for the day when nation would not lift up sword against nation and people would no longer learn how to wage war (Isa. 2:4). War in those times was at best an interim ethic, acceptable until human civilisation could outlaw it for good.
Has the problem been exacerbated by modern weapons technology? When nuclear weapons were developed, the English historian, Arthur Bryant, said, “If the nuclear weapon is ever used, those who survive will almost certainly live in a wilderness, and civilisation, as we know it, will end, at any rate for many years or generations. And if the nuclear weapon is not used, it may well be that liberty, as we know it, will also perish from the earth. The real problem is not how to ensure the survival of the human race, but how to ensure the simultaneous survival of both civilised society and human and political liberty.”
Modern weaponry has moved even further ahead since Arthur Bryant wrote, and the stakes are even higher. But the dilemma remains the same. If we use the weapons that are now available, we risk turning civilisation into a wilderness. That would contravene the Biblical principle, “God created the world not to be laid waste: He formed it to be inhabited” (Isa. 45:18). If on the other hand we refrain from using these weapons, human and political liberty may not survive.
Facing this dilemma, Jewish ethics would be likely to say that until higher standards prevail in the world, failure to act would be tantamount to moral abdication, and some wars have to be regarded as morally permitted.
But there is a “but”. War must always be a last resort. It must never be regarded as an inevitability. It must be at best an imperfect method of addressing human problems. The long-term aim must always be to work towards a world where “none shall hurt and none shall destroy” (Isa. 11:9), a world where swords become ploughshares and spears become pruning hooks (Isa. 2:4), where our energies and abilities are harnessed for peaceful ends.