Studied the effect of modern missile warfare (MMW) on self-reported sleep quality, stress, fear, depressed mood (DPM), fatigue, and power of concentration (CN). 1,045 Israelis aged ≥16 yrs were first surveyed during the 1991 Gulf War and then interviewed, except for chronic insomniacs, 30 days after the war. During the war, 51% of the Ss claimed to be suffering from disturbed sleep. Whereas 13% of the survey population had been chronic insomniacs before the war, 38% developed insomnia (IN) during the war. The war provoked reported stress, DPM, difficulties in CN, and increased fatigue. A month after the war ended, 19% of the previously normal Ss were still suffering from IN; 5% of IN cases were developed postbellum. Stress, depressed mood, and impaired CN correlated significantly with subjectively evaluated IN. MMW may induce long-term IN in a third of the population under threat. The risk of developing long-lasting IN is higher in those who reported having prolonged stress and DPMs.