A week after the 9-11 attacks, five threatening anonymous letters were sent to media outlets. Two weeks later, reporter Robert Stevens became the first person to die from inhaling anthrax that was enclosed with the letters. The case widened as anthrax-laden letters were sent to two Senators—one of the letters arrived at a Capitol Hill office and the other was routed to a mail facility, where it infected postal workers. Before the terror ended, 22 people developed infections and five died.
In response, the federal government set up the BioWatch program, an early warning network of sensors that would detect biological attacks before widespread public infection could occur. By the time President George W. Bush publicly announced the program in 2003, BioWatch filters had been deployed in 31 cities and more than $60 million had been spent on the program.
The program came under criticism early on. In 2003, a congressional report raised concerns about almost every aspect of BioWatch, from the funding to the implementation to the scope of coverage. Today, more than $1 billion has been spent on the program, which has expanded to 34 cities across the United States, yet the concerns about the program remain.