From the Executive Summary: "The longstanding efforts of the international community writ large to exclude weapons of mass destruction (WMD) from international competition and conflict could be undermined in 2030. The proliferation of these weapons is likely to be harder to prevent and thus potentially more prevalent. Nuclear weapons are likely to play a more significant role in the international security environment, and current constraints on the proliferation and use of chemical and biological weapons could diminish. There will be greater scope for WMD terrorism, though it is not possible to predict the frequency or severity of any future employment of WMD. New forms of WMD--beyond chemical, biological, radiological, and nuclear weapons--are unlikely to emerge by 2030, but cyber weapons will probably be capable of inflicting such widespread disruption that the United States may become as reliant on the threat to impose unacceptable costs to deter large-scale cyber attack as it currently is to deter the use of WMD. The definition of 'weapons of mass destruction' will remain uncertain and controversial in 2030, and its value as an analytic category will be increasingly open to question."
Center for the Study of Weapons of Mass Destruction, Occasional Paper 10
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