One question--isn't plutonium usually associated with fusion devices? I would assume that a suitcase unit would be a fission device (which could be smaller) using U-238???
Actually your correct. Looking at the age of those suitcase bombs, they probably were fission devices made out of U-235 or U-238. The radio-active core would still break down over time though. I dont know the specifics of nuclear technology; I did write a paper on it in Highschool, whats where I learned how the radio-active cores slowly break down.
