Medium Atomic Demolition Munition (MADM) was a tactical nuclear weapon developed by the United States during the Cold War. They were designed to be used as nuclear land mines and for other tactical purposes, with a relatively low explosive yield from a W45 warhead, between 1 and 15 kilotons. Each MADM weighed around 400 lb (181 kg) total. They were produced between 1965 and 1986.
http://en.wikipedia.org/wiki/Medium_Atomic_Demolition_Munition
Overkill
Overkill is the use of excessive force or action that goes further than is necessary to achieve its goal, most commonly in acts of violence.
Nuclear weapons
Overkill is especially used to refer to a destructive nuclear capacity exceeding the amount needed to destroy an enemy.
The term is attested from 1946 and was in common use during the Cold War era, referring to the arms race between the United States and the Soviet Union. Both nations possessed (US and Russia still possess) more than enough nuclear weapons to destroy one another many times over — nuclear overkill.
US policy was to be able to drop a nuclear bomb on every Soviet town and city forty times over; the term for this was "pounding the rubble" or, as military officers sometimes joked, "pounding the ruble".

1 Comment
Saint J.M. Browning
overkill is right. Nuclear landmine? Damn!