John Parachini divides his time between the Henry L. Stimson Center and the Monterey Institute's Center for Nonproliferation Studies.

The 1993 World Trade Center bombing, followed in the spring of 1995 by the Tokyo subway sarin nerve-gas attack and the bombing of a federal building in Oklahoma City, marks an ugly new threat for complex, open societies. In all three instances, perpetrators of the attacks sought to inflict mass casualties.

Past terrorist attacks generally struck discrete but indiscriminate targets, killing for political objectives. This new terrorist behavior pattern has understandably evoked considerable federal, state and local government attention, funding and action. Moreover, in 1998, the FBI handled 86 threats or actual cases of terrorism involving nuclear, biological or chemical weapons through September, which is already 20 more cases than 1997.

While the prospect of an attack with a weapon of mass destruction (WMD) is horrific, fortunately it is neither as easy to implement nor as inevitable as many suggest. Despite our societal vulnerability and the frightening killing capacity of these weapons, surprisingly few terrorist attacks have killed Americans.

Who is the threat?

Drunken drivers kill far more Americans every year than terrorists. Moreover, law-enforcement authorities have been remarkably successful in apprehending those few terrorists who have actually committed such crimes. Thus, the flurry of concern over WMD terrorism seems to be driven more by concern of our society's vulnerabilities rather than a thorough review of past incidents, current threats and real difficulties terrorist face when trying to use nuclear, chemical or biological weapons.

With potential adversary states such as Iraq and North Korea, the United States must maintain vigilance against state-sponsored terrorists who might conduct attacks on American soil to divert the attention of our civilian and military leaders, particularly during a foreign crisis. At various times since the Gulf War, Iraqi leader Saddam Hussein threatened that every Iraqi could serve as "a missile that can cross to countries and cities."

Yet a nation-state is not likely to attack the American homeland with weapons of mass destruction for fear of devastating retribution. Even a brutal dictator like Saddam most likely would hesitate to do something that would cause horrific destruction on his government.

Terrorists alligned with a "community of belief"

Conversely, non-state terrorists, like those loosely aligned with Osama bin Laden or Oklahoma City bomber Timothy McVeigh, might be unrestrained by the instincts of survival characteristic of nation-states. What we should fear most is a terrorist not associated with a government, but one aligned with a "community of belief" and bent on inflicting indiscriminate and mass casualties.

While the specter of terrorists acquiring chemical or biological weapons capability is unlikely, it is clearly within the realm of possibility. In the World Trade Center bombing, those responsible considered lacing their device with a potent chemical to create a deadly gas but opted not to do so. And in Tokyo, cultists made potent sarin nerve gas that was 20% pure but failed to disseminate the agent effectively and, fortunately, caused far fewer casualties.

Gaps in medical defense preparedness

While the national-security community inside and outside the U.S. government, and "first responders" such as local firefighters, police and emergency-response personnel, already are engaged in addressing the terrorist armed with weapons of mass destruction, the medical community is only starting to enter the fray. Given the critically important role emergency room doctors and nurses would have to play in treating casualties, the medical community's participation in planning and training for the eventuality of a terrorist attack, especially biological weapons, is extremely important.

A greater investment in the country's medical infrastructure can help with non-terrorist health problems such as the early detection of infectious diseases. Gaining the active participation of the medical community in the national effort to address chemical and biological terrorism and investing in the community's infrastructure will benefit society even if a terrorist attack remains remote. Vaccine stockpiling, emergency-service training and disease detection are just a few of the key problems that policymakers are attempting to address, but with the advice of only a small number of the medical community.

Investment in terrorism prevention and response is a multi-billion-dollar question. Regardless of the likelihood of a terrorist incident, no elected leader should argue for parsimoniousness when lives may be at stake. Even accepting that the likelihood of such an attack is remote, the consequences of inadequate preparation are potentially catastrophic.

In 1999, the federal government will allocate some $7 billion to combating terrorism, $4.3 billion of which will go to the Defense Department. On balance, this allocation seems appropriate because our armed forces possess considerable skill in combating weapons of mass destruction and operating in environments after these weapons have been used.

And importantly, our military forces deployed overseas face the greatest risk of being attacked by terrorists. However, a number of leading medical professionals argue persuasively that a modest increase in federal spending designed to upgrade our emergency medical-services infrastructure could make an enormous life-saving difference in the event of a terrorist attack with biological weapons.

The need for local leadership

A story that has been retold in Washington tells of President Clinton reading a frightening fictional account of a biological-weapons terrorist attack and then calling for more governmental actions to address the problem. Typical of this administration, the effort has been characterized by a well-meaning desire to act, but a lack of thorough, painstaking examination, rigorous coordination or sustained, high-level political attention to the problem.

In the current scandal-plagued political environment, the best we can probably hope for is that able people at the federal, state and local levels who catch the criminals, rescue the injured and plan for catastrophe will keep moving ahead. Hopefully, the national leadership will follow.