SDI Makes Moral Sense, Too : It Responds to the Requirements of Just-War Principles

Since President Reagan announced his Strategic Defense Initiative four years ago, commentators have analyzed its technical feasibility and political advisability.

Critics have paid little attention, however, to the moral argument for SDI. Yet the concept of strategic defense conforms to the principles of the 15-century-old tradition of just war.

Writing in 1960, before technology could actually make possible the limitation of nuclear war and, gradually, a diminished role for nuclear weapons in world politics, Jesuit theologian John Courtney Murray affirmed the “moral imperative” of limiting war. Today the promise of SDI offers a response to the moral requirements of just-war principles.

Just-war philosophy and its relationship to jus belli (law of war) has been articulated and defined in numerous modern documents. Most recently the American Catholic bishops, in their pastoral letter on war and peace, stimulated several principles for jus ad bellum (when resort to war is permissible) and others for jus in bello (permissible conduct in war).

In the nuclear age, just-war adherents consider that the critical principles are proportionality, probability of success and discrimination.

Proportionality would apply to jus ad bellum-- the harm inflicted and suffered must be commensurate with the good to be obtained--and to jus in bello-- the response to aggression cannot exceed the nature of it; hence, unlimited nuclear war would lack reasonable proportion.

For the just-war philosopher, the probability of success, a corollary of proportionality, would rule out an utterly futile, reckless resistance to aggression when the reasonably expected outcome would be entirely disproportionate to any good achieved, although a struggle even against great odds may be justified by a grave threat to continued existence.

Discrimination applied to jus in bello would require that noncombatant life may not be directly and intentionally taken.

The principle of strategic defense satisfies these moral requirements of natural reason. A defense designed to intercept missiles strengthens deterrence and adheres to the principles of proportionality and discrimination; at the same time, it permits a shift from exclusive reliance on offensive retaliation to a system of security based primarily on defense. By its nature, defense observes the principle of discrimination because it destroys only enemy nuclear weapons and imposes no harm on innocent, noncombatant life.

Defense also respects proportionality, since it inflicts damage only on enemy military forces and necessarily lessens the suffering incurred by the victim of aggression. A non-nuclear defense, moreover, clearly does not exceed the nature of nuclear aggression. Defense, even if partially effective, reduces the incentive to aggression in the first instance. If deterrence fails, it then decreases, rather than enlarges, the consequences of nuclear war.

Defense further upholds proportionality by enhancing the probability of success. Even an imperfect defense offers a better prospect of success than none at all, and this is manifestly the case if the enemy possesses even limited means of defense. It is difficult to imagine a reasonable moral argument against making nuclear war less likely or, should it occur, less destructive.

Our present moral and strategic situation is not without precedent. Only 50 years before President Reagan proposed his Strategic Defense Initiative, Great Britain found itself in similar circumstances. Prime Minister Stanley Baldwin’s remark in 1932 that “the bomber will always get through” expressed the prevailing belief in bomber invincibility during the 1930s. Winston Churchill recognized that until new means of defense were created, Britain would be compelled to depend on retaliatory air bombardment as its deterrent. In a House of Commons speech on Nov. 28, 1934, Churchill objected to exclusive reliance on offensive retaliation and summoned his countrymen to construct an anti-bomber defense: “Certainly nothing is more necessary, not only to this country but to all peace-loving and peace-interested powers in the world and to world civilization, than that the good old Earth should acquire some means or methods of destroying sky marauders.”

Churchill argued that effective defense would be morally preferable to a balance of terror maintained by a mutual-hostage relation between civilian populations.

Then, as today, strategic concerns reinforced moral considerations. Churchill warned that the Germans were moving rapidly with defensive preparations and that this development, if left unanswered, would upset stable deterrence.

In the 1930s Britons developed radar and fighter aircraft, which saved them in the Battle of Britain and bought time for an eventual Allied victory.

In our time, particularly in view of the massive and sustained Soviet program in strategic defense, prudent defensive measures can protect “the good old Earth” from ballistic missile “sky marauders.” SDI offers the West a means of security that makes both strategic and moral sense.