Many developing countries see biological weapons--like chemical weapons--as having a twofold utility: as a "poor man's atomic bomb," intended to deter attacks from stronger, unconventionally armed neighbors; and as a relatively cheap force multiplier that can help compensate for shortcomings in conventional arsenals.
Because much of the same biotechnology equipment employed by modern pharmaceutical programs or laboratories associated with modern hospitals can be used to foster a biological weapons program, identification of an offensive biological warfare program can be extremely difficult. Most equipment used in BW-related programs has legitimate applications, providing potential proliferators with the ability to conceal BW activity within legitimate research and development and industrial programs. The manufacture of vaccines for human or veterinary use can camouflage the production of large quantities of BW agents.
A number of experts speculate that terrorists might acquire biological agents more easily than chemical agents. And both BW and CW would be far easier to develop than nuclear weapons.
BW agents differ widely in infectiousness, length of incubation period, and lethality.
BW agents are relatively easy and inexpensive to produce for any nation that has a modestly sophisticated pharmaceutical or fermentation industry. Mass-production methods for growing cultures are widely used in the commercial production of yogurt, yeast, beer, antibiotics, and vaccines. Almost all equipment needed for the production of pathogens and toxins is dual-use and available on the international market, increasing the potential for concealing illicit activities under the cover of legitimate production.
BW agents are nonvolatile solids that would be disseminated either as a liquid slurry or a dry powder of freeze-dried organisms or toxin. Possible delivery systems range in complexity and effectiveness from an agricultural sprayer mounted on a truck to a specialized cluster warhead carried on a ballistic missile. The key to producing large-scale respiratory infections is to generate an aerosol or stable cloud of suspended microscopic droplets, each containing from one to thousands of bacterial or virus particles. Fogs and smokes are examples of visible aerosols.