America has committed itself to wage war against the terrorists who committed the beastly attacks on the World Trade Center and the Pentagon. That response is entirely justified, and Americans should maintain a steadfast determination to pursue the war to victory. It is imperative, though, that we identify our enemy clearly and realistically and not launch an amorphous global crusade.

Unfortunately, some of the statements coming from Bush administration officials are not reassuring on that score. Secretary of State Colin Powell has stated that the U.S. goal is nothing less than to rid the world of the “evil of terrorism.” President Bush even described America’s war effort as a “crusade,” a term that has an extremely negative historical connotation throughout the Islamic world. (Muslims well remember the medieval Christian Crusaders who invaded and occupied some of their lands in the Middle East.)

Agitated pundits also advocate a war against “terror states” and terrorist organizations everywhere in the world. Although such calls may be emotionally satisfying, they violate the most fundamental rule of good foreign policy: the requirement that the objective pursued must be attainable.

If Secretary Powell is taken at his word, America’s war aims would be daunting indeed. Even if the United States confined its campaign to countries listed by the State Department as sponsors of international terrorism, and organizations designated as terrorist entities, the roster of enemies would be breathtakingly long. It would include seven countries (Cuba, Iran, Iraq, Syria, North Korea, Libya, and Sudan) and more than 30 organizations. Waging a war on that scale would be far beyond what the American people have contemplated.

Moreover, the State Department list is far from complete. Curiously, Afghanistan is not listed as a state sponsor of terrorism. Nor (for political reasons) are such U.S. “friends” as Saudi Arabia and Pakistan, even though both governments have funded extremely dubious organizations for years. The roster of terrorist organizations itself continues to expand steadily. A few weeks ago, the right-wing United Self-Defense Forces of Colombia was added.

Waging a global crusade against terrorism would require the United States to fight an assortment of organizations that, while often vile, have never seemed to regard this country as their enemy. Would America really want to go out of its way to take on the Irish Republican Army, the Basque separatists in Spain, the Tamil Tigers in Sri Lanka, or Colombia’s United Self-Defense Forces? What would be the possible gain from acquiring enemies where they do not now exist?

The suspicion persists that most officials and pundits who call for a comprehensive campaign against terrorism really mean a campaign against ISLAMIC terrorism. But that focus has its own problems. If the United States goes after only Islamic organizations and states, it will become next to impossible to convince Muslims around the world that the campaign is not a holy war by the West against their faith, using the fight against terrorism as a pretext. That perception would have ugly ramifications that could plague America for decades.

International political realities will probably compel the Bush administration to abandon loose rhetoric and focus its substantive efforts on the real task: identifying and eradicating the parties responsible for the atrocities committed on September 11 (probably Osama bin Laden and his Taliban sponsors in Afghanistan). Going beyond that objective would not only risk fracturing the international coalition that Washington is laboring to assemble, but it would soon be seen by most U.S. military planners as impractical.

Those who are unsatisfied by such limited war aims should remember America’s policy during that most destructive of conflicts, World War II. The United States declared war on Japan and Germany; it did not declare war on dictatorship. Indeed, America did not even declare war on fascism. The United States never took military action against Spain’s Francisco Franco or Argentina’s Juan Peron. Both were odious rulers, and they certainly did not wish America well, but they did not make themselves overt enemies of the United States.

A similar approach ought to be adopted in the current crisis. Any party that attacks the United States is fair game for retaliation. But America should not take action against parties that, however much they might dislike the United States, have not harmed us. Achieving victory over those who have harmed us will be a difficult enough challenge.