Originally posted by: rahvin
What I can't understand is why people think nuclear weapons are tiny little things. Plutonium required for a nuke weighs 10 kilos (25 pounds), to get it to explode you have to pack explosives around it, many many pounds of explosives, they have to be very special explosives with many layers of fast and slow burn layered so that the implosion is uniform or all you will do is blow the polutonium around and not into a supercritical mass. If you don't have access to high tech explosives you have to use a lot more of the lower grades. A hand built plutonium nuke is going to weigh a couple hundered pounds without shielding and without that shielding anyone around the thing is going to die of radiation exposure, with a probable lethal exposure in hours. With shiedling the thing is going to weigh a half a ton.
And that's if you have plutonium, critical mass for uranium is IIRC around 100 pounds. Everyone talks about "suitcase nukes" but even the low yield tactical nukes that the US planned to use against a soviet invasion of europe weighed in excess of 250 pounds (and they were a lot higher tech than something Al Queda would be able to build). The idea of them smuggling a nuke in is quite silly. I'm not going to deny it's possible (ala what happened in true lies) where a large nuke is smuggled in, but the probability is just miniscule and frankly where I live I don't need to be worried at all.