Aimed in the right direction, the U.S. M18A1 Claymore mine is one of the most lethal and devastating anti-infiltration weapons of modern warfare. There’s a reason for the qualifier on that kudo, and more about that in a moment. From its initial employment with U.S. forces in the mid-1950s, the Claymore gave infantry units a reliable and deadly device that could be used in perimeter defense or offensively as an ambush trigger.