In the 1950s, while in South America military-like brigades were hunting down Aedes aegypti, in the United States, the Army was falling in love with the same mosquito. At Fort Detrick, the military’s biological weapons base in Maryland, in great secret, Army scientists were considering how fleas, grasshoppers, and mosquitoes might be deployed against the Communist threat. These insects were harder to protect against than gas— masks wouldn’t help. The threat they posed would last, as long as a population of insects remained alive. Plus, it would be very difficult to pin an insect-borne attack on the U.S.