Due to the surprise nature of sniper fire, high lethality of aimed shots and frustration at the inability to locate and counterattack snipers, sniper tactics have a significant negative effect on morale. Extensive use of sniper tactics can be used to induce constant stress and fear in opposing forces, making them afraid to move about or leave cover. In many ways, the psychological impact imposed by snipers is quite similar to those of landmines, booby-traps, and IEDs (constant threat, high "per event" lethality, inability to strike back).