The world's terrorists are further away than that still to this day, and my simple point was only that the issues involved were non-trivial, anyway.
Only in the movies. Working with such brittle, dangerous metals as Uranium is anything but trivial
Not to belabor my point, but al Qaeda operatives are not exactly concerned about personal safety. And yes, a 110 pound HEU bomb is pretty trivial since that's all that's required for supercritical mass. The high tech solutions requiring neutron exciters come in when you're dealing with Uranium-235 quantities in less than natural critical mass.
Likewise, the electronics and conventional explosives used to start the detonation are all impacted negatively by the emitted radiation of the fissionable material, among other such problems.
These are all part and parcel of safety considerations with which al Qaeda operatives do not even bother concerning themselves. Moreover, lead is not hard to come by and has been previously used for radioactive shielding in such weaponry.
Consider that NAZI Germany couldn't figure out how to overcome these hurdles during WW2, though not for lack of trying.
Nazi Germany failed in its pursuit of the atomic bomb because their scientists started out by trying to prove a Jew (Einstein) was wrong. The Nazi ideology doomed their work from the start.
Neither could Soviet Russia or the UK at that time, either.
Soviet Russia was less than 5 years away from their own A-bomb when the Rosenbergs forked over our secrets to them. The main thing holding them back was that they lacked the core research infrastructure we had cultivated over the entirety of the Manhattan Project.
The world's terrorists are further away than that still to this day, and my simple point was only that the issues involved were non-trivial, anyway.
"Not to belabor my point, but al Qaeda operatives are not exactly concerned about personal safety. And yes, a 110 pound HEU bomb is pretty trivial since that's all that's required for supercritical mass."
There is more to it than mere personal safety. The precise shape of the core is rather important, and working with the brittle, dangerous metals that are used for nukes is anything but trivial. Get the shape a little bit wrong and you are going to get a fizzle rather than a BOOM.