Because it was desigbed to "make a whole area kill or incapacitate advancing troop formations and irradiate the area so that it was uninhabitable for up to 48 hours, long enough to mobilize NATO forces." Not much fun to game out to me. The Special Atomic Demolition Munition isn't much fun either.
from website that photo came from with text.
http://en.wikipedia.org/wiki/Davy_Cr...lear_device%29
One of the smallest nuclear weapons ever fielded, the Davy Crockett was developed in the late 1950s for use in a tactical confrontation with Soviet troops in West Germany. Small teams of the Atomic Battle Group (charged with operating the device) would be stationed every few kilometers to guard against Soviet attack, using the power of their nuclear artillery shells to kill or incapacitate advancing troop formations and irradiate the area so that it was uninhabitable for up to 48 hours, long enough to mobilize NATO forces.
The M-388 round used a heavy version of the W54 warhead, a very small sub-kiloton fission device. The W54 weighed about 51 lb (23 kg), with a selectable yield of 10 - 250 tons (very close to the minimum practical size and yield for a fission warhead). The complete round weighed 76 lb (34.5 kg). It was 31 in (78.7 cm) long with a diameter of 11 in (28 cm) at its widest point; a subcaliber piston at the back of the shell was actually inserted into the launcher's barrel for firing.
The Davy Crockett could be launched from either of two launchers: the 4-inch (102 mm) M28, with a range of about 1.25 mi (2 km), or the 6-in (155 mm) M29, with a range of 2.5 mi (4 km). Both weapons used the same projectile, and could be mounted on a tripod launcher or carried by truck or armored personnel carrier. They were operated by a three-man crew.
Both recoilless rifles proved to have poor accuracy in testing, so the shell's greatest effect would have been its extreme radiation hazard. Even at a low yield setting, the M388 would produce an almost instantly lethal radiation dosage (in excess of 10,000 rem) within 500 feet (150 m), and a probably fatal dose (around 600 rem) within a quarter mile (400 meters). With no shielding or protection from either blast or radiation, a Davy Crockett crew would have been unlikely to survive an engagement without long-term health risks.
The warhead was tested on July 7, 1962 in the LITTLE FELLER II weapons effects test shot, and again in an actual firing of the Davy Crockett from distance of 1.7 miles (2.72 km) in the "SMALL BOY" test shot (LITTLE FELLER I) on July 17. This was the last atmospheric test detonation at the Nevada Test Site.
Production of the Davy Crockett began in 1956. 2,100 were produced. The weapon was deployed with U.S. Army forces from 1961 to 1971.
Versions of the W54 warhead were also used in the Special Atomic Demolition Munition project and the AIM-26A Falcon.