... but its not? Literally, the "harder" part about making a bomb with reactor-grade material is keeping it from blowing-up prematurely, while still getting maximum yeild at boom-boom time.
A less-advanced nation might get a lesser explosion out of a "safer"(doesn't explode until its supposed to) bomb with reactor-grade material, but its still going to be a massive, nuclear explosion, and the unspent fuel creates additional radio-active fallout.
Apparently, civilized-countries' worst nightmare regarding weapons-grade plutonium is that those that "shouldn't" have "the bomb" could build them and then be able to shelve them for a later, legitimate threat. Oh, and not being able to cry "they built a dirty bomb!!" if such were ever used.
"stays"!? You mean "after magically becomming so over-night", right, buddy!? I'll tell you now, if you trick me/force me to spend time with any AI, I'm doing everything I can to radicallize that fucker into being as human as any of us.
Notice I didn't say "humane", because that we aren't really, and I will gladly take a bullet to get AIs targetting morons like this man, and the others like him, who seek to enrich themselves by way of continuing to treat the rest of us as disposable and irrelavent.