Despite a growing concern over bioterrorism in general, as well as scattered incidents involving domestic extremists and biological or chemical agents, American concern about anthrax in the 1980s and early 1990s remained at a relatively low level. Certainly there was little hysteria or hype. However, several events in the 1990s drastically increased both concern and publicity over anthrax, oversensitizing the American public to the dangers of anthrax in the hands of extremists or terrorists and resulting by the end of the decade in a frustrating rash of anthrax hoaxes that, ironically, only fueled the publicity fire still further. By the beginning of the 21st century it had become abundantly clear that the U.S. had developed an almost primal fear of anthrax – and anybody who wanted to throw the country into a panic need look no further for an instrument with which to do so.

The event that really introduced anthrax into the public consciousness was the Gulf War. Reports had emerged during the 1980s that the Iraq government had used chemical agents both against Iran during the Iran-Iraq War and against the discontented Kurdish minority in its own country. By the end of the decade, U.S. and Israeli intelligence services had developed strong evidence of an Iraqi biological and chemical weapons program. W. Seth Carus, at the time a researcher at the Washington Institute for Near East Policy, estimated in 1989 that Iraq had the capacity to produce a thousand tons of chemical agents annually. Early that same year, the Reagan administration formally acknowledged that Iraq was completing construction of a biological weapons plant and expressed "concern and displeasure" to Saddam Hussein.

Even after the Gulf War, though, anthrax was more the stuff of thrillers than a real concern. Although the threat of anthrax was highly publicized in 1990-1991, Saddam Hussein refrained from using the biological agent against a people far more capable of massive retaliation than the Iranians or Kurds. Terrorist attacks like the bombing of the World Trade Center in 1993 raised American concerns about terrorists, but that act involved conventional weapons. However, in 1995 the U.S. experienced a "one-two punch" that raised its concerns about biological and chemical terrorism.

Ironically, neither "punch" involved biological or chemical weapons use in the U.S. Nevertheless, together they had a tremendous impact. The first event was the March 20, 1995, use of nerve gas by the Aum Shinrikyo sect on the Tokyo subway in Japan. The Sarin attack killed 12 people and hospitalized thousands more.

The March 20 episode actually turned out to be the latest in a series of efforts by Aum Shinrikyo to release agents such as botulinum and anthrax in government buildings and public places, but every previous effort had ended in failure – so much so that authorities were not aware they had taken place. Aum Shinrikyo was the first terrorist group to attempt to kill using anthrax, but had not taken a single life with the disease.

Nevertheless, the event sent shockwaves around the world and caused people in many countries to wonder if their own borders harbored people with the capacity and desire to cause such mass casualties. For the U.S. that question was answered only a single month later when, on April 19, 1995, anti-government extremists Timothy McVeigh and Terry Nichols used a fertilizer bomb to destroy the Murrah Federal Building in Oklahoma City, killing 168 people and injuring hundreds more. It was the worst terrorist act up to that point in U.S. history.

What was more, Americans soon realized that McVeigh and Nichols were hardly alone. In the early to mid-1990s the extreme right in the U.S. experienced a major resurgence. Not only were many older groups such as neo-Nazis given new energy, but entirely new movements emerged, such as the militia movement and the common law court movement. McVeigh and Nichols used conventional explosives to perpetrate their terrorist act but perhaps the next Timothy McVeigh would use nerve gas or plague or anthrax.

The combination of the Aum Shinrikyo incident and the Oklahoma City bombing heightened U.S. concern over biological and chemical agents to new levels, a concern that rhetoric soon reflected. "To build a really devastating anthrax weapon," one defense expert told a Pittsburgh newspaper, "takes less money and skill than the Oklahoma City bomb…A fertilizer bomb kills by the hundreds. A biological weapon kills by the tens of thousands." The Tokyo gas attack was a "wake-up call," according to Deputy Secretary of Defense John Hamre, "to us and the entire world, that people in the future are going to use these rather terrible weapons in ways that potentially just bring an entire city to its knees." In late 1995, Dr. Gordon C. Oehler, Director of the CIA’s Nonproliferation Center, testified to Congress that "extremist groups worldwide are increasingly learning how to manufacture chemical and biological agents, and the potential for additional chemical and biological attacks by such groups continues to grow."

Such statements were often accompanied by extreme scenarios. The Office of Technology Assessment issued a report in 1993 suggesting that a small plane flying over Washington D.C. could use 100kg of anthrax and a crop sprayer to kill up to three million people. A few years later, in 1997, Secretary of Defense William Cohen held up a five-pound bag of sugar at a press conference to illustrate how little anthrax would be needed to devastate Washington, D.C. Richard Preston, who had written a sensationalistic book on the Ebola virus and a 1997 novel, The Cobra Event, about a bioterrorism event in New York City, grew to stature high enough to address Congress on the subject in 1998.