Coordinated, comprehensive resistance to terrorism may be a new kind of war, but terrorism, alas, is all too familiar, and some age-old principles apply to fighting it. Let's start with basics: How should we regard the violence of war in general? Common sense says that in a fallen world, justice requires the support of force. God Himself seemed to approve its use in the wars of ancient Israel. But this is not ancient Israel, and the word of God also teaches that we must never "do evil that good may come." Besides, there are all those other troubling passages-the Sixth Commandment and the warning that "All who take the sword shall perish by the sword." So where does all this leave us? Is there such a thing as a justified war? The first thing to remember is that no matter how we answer, there is no political solution to the problem of sin. Not even a justified war could end all wars; not even pacifism could bring a lasting peace. So our first concern about terrorism, even before our political concerns, should be what we can do to support ambassadors of the gospel, and those other people of good will, who care for the people who suffer. But that doesn't allow us to dodge the question about justified war, does it? It's true that we are citizens of heaven, but we don't yet live there. Even though political concerns come second, we do have political concerns. So, when asked to bear the sword, we cannot simply change the subject; we must answer either yes or no. Which answer should we give? For most of the Christian era, most Christians have believed that the Sixth Commandment and the warning against "taking the sword" do not prohibit every kind of killing, but murder. They mean that we must never deliberately take innocent human life, we must never take even guilty human life except by public authority in pursuit of justice, and we must never put our ultimate trust in violence. Can lethal force ever satisfy these conditions? The Apostle Paul thought so. As he taught in Romans 13, the ruler "does not bear the sword for nothing. He is God's servant, an agent of wrath to bring punishment on the wrongdoer." How does this apply to war? Beginning with the great church father Augustine (a.d. 354-430), Christian thinkers have developed criteria for distinguishing justified from unjustified wars. We can use them as a kind of checklist in situations where decisions must be made about government violence. This list does not spare us the need for hard judgment, but it tells us which hard judgments we need to make. First come criteria for when going to war is permissible. It isn't enough to honor most of them; all seven must be satisfied. Public authority: War must be declared by a legitimate government. It is not for private individuals and groups to decide when lethal violence must be used in support of justice. Most terrorist groups are private, although they receive various kinds of help from governments which hide behind them. Terrorist acts are wrong, however, even if they are committed by a government-not because of the principle of public authority, but for other reasons, stated below. Just Cause: War must not be waged except to protect innocent life, to ensure that people can live decently, and to secure their natural rights. Needless to say, this would not authorize the aim of destroying entire groups in a hated population. Right Intention (first part-more later): Not only must there be just cause to take up arms; this just cause must be the reason for taking up arms. Our goal must be to achieve a just peace-not to pump up the economy or keep gasoline prices low. Comparative Justice: War should not be waged unless the evils that are fought are grave enough to justify killing. Notice the word: "Killing," not "murder." Murder is deliberately taking innocent human life. This is categorically forbidden, even in wartime. Proportionality (first part-more later): There must be reason to expect that going to war will end more evil than it causes. This means not only physical evil, but spiritual-not only destruction of bodies and buildings, but corruption of callings and virtues. Probability of Success: There must be a reasonable likelihood that the war will achieve its aims. Last Resort: War should not be waged unless a reasonable person would recognize that the peaceful alternatives have been exhausted. There comes a point, though, when even a reasonable person recognizes that the opponent is not interested in peace. Next come criteria for how war must be fought. No exceptions are allowed, no matter how much we may want to make them. Right Intention (second part): Remember, the goal must be to achieve a just peace. Therefore, we must avoid any act or demand that would make it more difficult for our enemies to reconcile with us some day. Of course, they may nurse hatreds of their own that would prevent their ever reconciling with us. But these are not our responsibility. Proportionality (second part): We must never use tactics that can be expected to bring about more evil than good. Discrimination: Even though harm might come to them accidentally, directly intended attacks on innocent bystanders are never permissible. The principles of justified war would certainly cramp our style. God is not interested in our style; what He demands of us is holiness. The fact that terrorists reject the principles does not justify us in violating them-not even to act against terrorism. By violating them, rather than ridding the world of terrorists we would merely make ourselves the biggest, strongest terrorists of all. Murder remains murder, even when the murdered man might justly have been executed. But not all lethal violence by legitimate government is murderous. We are not forbidden to make war against warmakers. Here are a few questions I have been asked in the difficult days following the bombing of the Pentagon and World Trade Center. Question: "The plethora of views I have heard about the anguishing events in New York and Washington leaves me perplexed. Psalm 37 accurately frames my confusion when it says, 'Do not fret because of the evil men or be envious of those who do wrong.'" Should we be angry? Reply: We should take David's psalm seriously-but we should also remember that David bore weapons as the authorized ruler of Israel. It is not for human beings to implement eternal justice, nor does it belong to us to gratify private anger. Vengeance belongs to God alone. However, God Himself requires us to implement temporal justice through legitimate public authority. When God ordained government, he did not ordain that it be impotent. Question: "A friend wrote to me, 'To extend reprisals to governments which harbor terrorists goes beyond the principles of justified war.' Do you agree?" Reply: Nothing in the principles of justified war implies such a conclusion. What your friend is really saying is that although we may punish the perpetrators of evil deeds, we may not punish the accessories to them. Would he take this view of ordinary criminal violence? Should the police apprehend a bank robber, but let the ones who supplied the gun, provided the safe house, and drove the getaway car go free? I doubt it. The culpability of accessories may be different than the culpability of perpetrators, and this is an important point. But let's not imagine that accessories are not culpable. Question: "If we bombed a country that harbored terrorists, I suspect that the victims would largely be civilians. Would it make a difference if we could pinpoint the government leaders there and bomb only the government offices?" Reply: The discrimination principle categorically forbids deliberately targeting innocent bystanders, but it does not forbid every act that might harm them unintentionally. It's also important to remember that the issue isn't who wears a uniform, but who shares responsibility for the evil we are trying to end. Government facilities that direct or support the perpetrators of unjust violence may certainly be targeted, even if the perpetrators themselves are somewhere else. Of course we are obligated to do what we can to reduce the risk of collateral harm, so indiscriminate bombing is out. The proportionality principle also kicks in, barring us from deeds that bring about more harm than they prevent. The principles of justified war do not make wartime moral questions easy. They say, "Here is how to answer the questions," not, "Here are the answers." That may not seem like much help. But it is enough.