The neither the Norks nor the Islamo-terrorists need an ICBM!
I used to worry that they could bring one into a US harbor in a yacht, or across the border in a truck. After reading this, they could probably use a bass boat, an old VW Beetle or strap it to the back of the seat on a Harley trike.
https://en.wikipedia.org/wiki/W80_(nuclear_warhead)
The W80 is physically quite small: the “physics package” itself is about the size of a conventional Mk.81 250-pound (110 kg) bomb, 11.8 inches (30 cm) in diameter and 31.4 inches (80 cm) long, and only slightly heavier at about 290 pounds (130 kg).
Armorers have the ability to select the yield of the resulting explosion in-flight, a capability referred to as variable yield. The minimum yield, perhaps using just the boosted fission primary, is around 5 kilotons of TNT; the highest yield is equivalent to around 150 kt.