Extinguishing the Threat

U.S. special weapons may target Iraqi chemical and biological threats

U.S. military forces may use a surprise one-two punch of secret weapons to neutralize Iraqi chemical and biological weapons of mass destruction in the event of war. The first, a high power microwave (HPM) burst delivered via a cruise missile or other guided munition, would act like an electronic lightning bolt to disrupt computerized command facilities as well as guidance systems aboard enemy missiles. The second knockout punch would be what the military calls an agent defeat weapon (ADW) that uses an incendiary explosive to first burn any harmful chemicals and biological toxins and then further inactivate them with chlorine and acid cleansers.

The U.S. military won't comment on these weapons, but defense analysts note that high-powered microwave and agent defeat weapons have been in development for some years, and it is probable that their development has been accelerated in recent months as the crisis with Iraq has intensified. Experts point to the rapid development of the bunker-busting thermobaric bombs used in Afghanistan as a precedent for using weapons still in the development stage.

Whether U.S. troops will face a biological or chemical threat in Iraq is unclear, say defense analysts like John Pike, director of GlobalSecurity.Org, and Michael Levi, director of the strategic security project of the Federation of American Scientists. They note the failure of United Nations inspectors to find chem/bio weapons in Iraq as well as persistent rumors that such weapons have been moved to another country. "What everyone says is that they've moved the stuff out of the country," Levi comments. "If we find their weapons of mass destruction, we're probably going to find them in Syria." Pike, meanwhile, credits Israeli intelligence services as the source of those rumors, calling it a disinformation campaign whose purpose is to put Syria next on the American hit list. "I have difficulty understanding how Israeli intelligence would have come into possession of such information," Pike states.


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Given such uncertainty, U.S. forces will at minimum be targeting enemy missile launchers. However, the mobile nature of many missile launchers makes them hard to find and harder to hit. It¿s likely then, Pike predicts, that American forces will target any suspect bio/chem facilities in the early hours of the war.

It is against suspect facilities that HPM and ADW weapons might be most effective. A HPM weapon generates a short, intense surge of electromagnetic (EMP) energy similar to that produced by a nuclear explosion. The EMP burst produces thousands of volts, which can penetrate through seams in a building and fry any unshielded semiconductors in the area. Although the effective blast area of a HPM weapon is much smaller than that of a nuclear weapon, its blast radius is still likely to measure in the hundreds of meters. This is larger than the blast area of more precisely targeted GPS or laser-guided bombs used against specific buildings. A HPM weapon would be useful against large-acreage targets like Saddam Hussein's presidential palaces, where the precise location of a chem/bio facility is unknown, Pike observes. HPM attacks are also stealthy--only a close inspection of the affected electronic components will reveal evidence of the assault.

But whether HPM weapons should be used in the vicinity of civilian facilities such as hospitals or mosques is a big issue that will be difficult to address. "Do I also kill all the Iraqis with pacemakers in a nearby mosque?" Pike remarks. "That's the type of question the U.S. will need to answer." [For more on HPM safety, see "Do Microwave Weapons Kill?]

Also potentially available are vehicle-mounted microwave guns, prototypes of which were developed by the U.S. Air Force at its Kirtland, New Mexico, base even before 9/11. A microwave gun would employ an electrical pulse to create a stream of high-energy particles that are accelerated into a cavity. The cavity causes the charged particles to "bunch," or accelerate coherently, creating electromagnetic radiation in the form of microwaves. A specially designed antenna would then target incoming missiles or mobile launchers.

Early versions of HPM weapons have already been used. During the Gulf War, the U.S. Navy reportedly used experimental warheads that converted conventional explosive energy into a microwave pulse that disrupted Iraqi communications networks. Col. William G. Heckathorn, former deputy director of the Directed Energy Directorate of the Air Force Research Laboratory, is credited with the innovation. The U.S. Air Force is also studying how to incorporate microwave weapons into its next generation of unmanned airborne planes.

HPM weapons may very well disrupt computer systems and other electronic devices that Iraqi command centers would use to activate chemical and biological weapons. Their main weakness is the inability of U.S. forces to judge their effectiveness in a timely fashion. "Battle damage assessment of HPM weapons is the biggest problem," Levi notes.

Destroying the actual chemical or biological material is a task that may fall to agent defeat weapons being developed by the U.S. Navy and Lockheed Martin under a program originally dubbed Vulcan Fire and now spearheaded by the secretive U.S. Defense Threat Reduction Agency. The HTI-J-1000, as it is called, would be the fill inside the penetrating warhead used on the massive 2,000-pound GBU-24 laser-guided bomb and BLU-109 Joint Direct Attack Munition (JDAM) used to attack underground bunkers. The titanium boron lithium perchlorate intermetallic fill would ignite to become a high temperature incendiary (HTI) that relies on a series of chemical reactions to increase the temperature inside the targeted bunker to 1,000 degrees Fahrenheit, causing storage tanks to explode. The intense heat destroys biological and chemical agents inside the tanks. In addition, the HTI-J-1000 chemical reactions produce by-products like chlorine, fluorine and a variety of acids that neutralize chem/bio agents much as disinfectants would. All these reactions occur at very low pressure to prevent the chem/bio agents from dispersing into the surrounding area before they can be eliminated.

Twenty HTI-J-1000 weapons were scheduled for readiness by 2004, so prototypes are probably available if needed for a war in Iraq, eerily following the same development cycle as the prototypical microwave weapons used in the Gulf War and the thermobaric bombs used in Afghanistan. Whether these weapons prove to be the magic bullets needed against chem/bio weapons, however, remains to be seen.

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